master
parent
bec8fe4850
commit
de656ad6b2
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@ -1,21 +0,0 @@
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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print(classes)
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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print(classes)
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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print(groups)
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print(classes)
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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print(groups)
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print(classes)
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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print(groups)
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print(classes)
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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print(groups)
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print(classes)
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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print(groups)
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print(classes)
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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for row in group:
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print(row[-1])
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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for row in group:
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print(row[-1])
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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# test Gini values
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
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for group in groups:
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size = float(len(group))
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# avoid divide by zero
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if size == 0:
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continue
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score = 0.0
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# score the group based on the score for each class
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for class_val in classes:
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p = [row[-1] for row in group].count(class_val) / size
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score += p * p
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# weight the group score by its relative size
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gini += (1.0 - score) * (size / n_instances)
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return gini
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# test Gini values
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print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
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print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
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def gini_index(groups, classes):
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# count all samples at split point
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n_instances = float(sum([len(group) for group in groups]))
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# sum weighted Gini index for each group
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gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
for row in group:
|
|
||||||
print(row[-1])
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,24 +0,0 @@
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
for row in group:
|
|
||||||
print(row[-1])
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,24 +0,0 @@
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
for row in group:
|
|
||||||
print(row[-1])
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,24 +0,0 @@
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
for row in group:
|
|
||||||
print(row[-1])
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,24 +0,0 @@
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
for row in group:
|
|
||||||
print(row[-1])
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,24 +0,0 @@
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
for row in group:
|
|
||||||
print(row[-1])
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,23 +0,0 @@
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,22 +0,0 @@
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# test Gini values
|
|
||||||
print(gini_index([[[1, 1], [1, 0]], [[1, 1], [1, 0]]], [0, 1]))
|
|
||||||
print(gini_index([[[1, 0], [1, 0]], [[1, 1], [1, 1]]], [0, 1]))
|
|
|
@ -1,54 +0,0 @@
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
print('X%d < %.3f Gini=%.3f' % ((index+1), row[index], gini))
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
dataset = [[2.771244718,1.784783929,0],
|
|
||||||
[1.728571309,1.169761413,0],
|
|
||||||
[3.678319846,2.81281357,0],
|
|
||||||
[3.961043357,2.61995032,0],
|
|
||||||
[2.999208922,2.209014212,0],
|
|
||||||
[7.497545867,3.162953546,1],
|
|
||||||
[9.00220326,3.339047188,1],
|
|
||||||
[7.444542326,0.476683375,1],
|
|
||||||
[10.12493903,3.234550982,1],
|
|
||||||
[6.642287351,3.319983761,1]]
|
|
||||||
split = get_split(dataset)
|
|
||||||
print('Split: [X%d < %.3f]' % ((split['index']+1), split['value']))
|
|
|
@ -1,48 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
|
|
||||||
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
print('X%d < %.3f Gini=%.3f' % ((index+1), row[index], gini))
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
dataset = pd.read_excel('dataset2.xls', sheet_name="forestfires").to_numpy()
|
|
||||||
split = get_split(dataset)
|
|
||||||
print('Split: [X%d < %.3f]' % ((split['index']+1), split['value']))
|
|
|
@ -1,48 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
|
|
||||||
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
print('X%d < %.3f Gini=%.3f' % ((index+1), row[index], gini))
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
dataset = pd.read_excel('train.xls', sheet_name="Sheet1").to_numpy()
|
|
||||||
split = get_split(dataset)
|
|
||||||
print('Split: [X%d < %.3f]' % ((split['index']+1), split['value']))
|
|
|
@ -1,48 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
|
|
||||||
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
print('X%d < %.3f Gini=%.3f' % ((index+1), row[index], gini))
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
split = get_split(dataset)
|
|
||||||
print('Split: [X%d < %.3f]' % ((split['index']+1), split['value']))
|
|
|
@ -1,48 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
|
|
||||||
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
print('X%d < %.3f Gini=%.3f' % ((index+1), row[index], gini))
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
split = get_split(dataset)
|
|
||||||
print('Split: [X%d < %.3f]' % ((split['index']+1), split['value']))
|
|
|
@ -1,90 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
|
||||||
outcomes = [row[-1] for row in group]
|
|
||||||
return max(set(outcomes), key=outcomes.count)
|
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
|
||||||
left, right = node['groups']
|
|
||||||
del(node['groups'])
|
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
|
||||||
return
|
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
|
||||||
return
|
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
|
||||||
node['left'] = to_terminal(left)
|
|
||||||
else:
|
|
||||||
node['left'] = get_split(left)
|
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
|
||||||
node['right'] = to_terminal(right)
|
|
||||||
else:
|
|
||||||
node['right'] = get_split(right)
|
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
|
||||||
root = get_split(train)
|
|
||||||
split(root, max_depth, min_size, 1)
|
|
||||||
return root
|
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
|
||||||
if isinstance(node, dict):
|
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
|
||||||
print_tree(node['left'], depth+1)
|
|
||||||
print_tree(node['right'], depth+1)
|
|
||||||
else:
|
|
||||||
print('%s[%s]' % ((depth*' ', node)))
|
|
||||||
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
tree = build_tree(dataset, 1, 1)
|
|
||||||
print_tree(tree)
|
|
|
@ -1,90 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
|
||||||
outcomes = [row[-1] for row in group]
|
|
||||||
return max(set(outcomes), key=outcomes.count)
|
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
|
||||||
left, right = node['groups']
|
|
||||||
del(node['groups'])
|
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
|
||||||
return
|
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
|
||||||
return
|
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
|
||||||
node['left'] = to_terminal(left)
|
|
||||||
else:
|
|
||||||
node['left'] = get_split(left)
|
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
|
||||||
node['right'] = to_terminal(right)
|
|
||||||
else:
|
|
||||||
node['right'] = get_split(right)
|
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
|
||||||
root = get_split(train)
|
|
||||||
split(root, max_depth, min_size, 1)
|
|
||||||
return root
|
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
|
||||||
if isinstance(node, dict):
|
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
|
||||||
print_tree(node['left'], depth+1)
|
|
||||||
print_tree(node['right'], depth+1)
|
|
||||||
else:
|
|
||||||
print('%s[%s]' % ((depth*' ', node)))
|
|
||||||
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
tree = build_tree(dataset, 5, 1)
|
|
||||||
print_tree(tree)
|
|
|
@ -1,90 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
|
||||||
outcomes = [row[-1] for row in group]
|
|
||||||
return max(set(outcomes), key=outcomes.count)
|
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
|
||||||
left, right = node['groups']
|
|
||||||
del(node['groups'])
|
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
|
||||||
return
|
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
|
||||||
return
|
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
|
||||||
node['left'] = to_terminal(left)
|
|
||||||
else:
|
|
||||||
node['left'] = get_split(left)
|
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
|
||||||
node['right'] = to_terminal(right)
|
|
||||||
else:
|
|
||||||
node['right'] = get_split(right)
|
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
|
||||||
root = get_split(train)
|
|
||||||
split(root, max_depth, min_size, 1)
|
|
||||||
return root
|
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
|
||||||
if isinstance(node, dict):
|
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
|
||||||
print_tree(node['left'], depth+1)
|
|
||||||
print_tree(node['right'], depth+1)
|
|
||||||
else:
|
|
||||||
print('%s[%s]' % ((depth*' ', node)))
|
|
||||||
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
tree = build_tree(dataset, 5, 1)
|
|
||||||
print_tree(tree)
|
|
|
@ -1,90 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
|
||||||
outcomes = [row[-1] for row in group]
|
|
||||||
return max(set(outcomes), key=outcomes.count)
|
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
|
||||||
left, right = node['groups']
|
|
||||||
del(node['groups'])
|
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
|
||||||
return
|
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
|
||||||
return
|
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
|
||||||
node['left'] = to_terminal(left)
|
|
||||||
else:
|
|
||||||
node['left'] = get_split(left)
|
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
|
||||||
node['right'] = to_terminal(right)
|
|
||||||
else:
|
|
||||||
node['right'] = get_split(right)
|
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
|
||||||
root = get_split(train)
|
|
||||||
split(root, max_depth, min_size, 1)
|
|
||||||
return root
|
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
|
||||||
if isinstance(node, dict):
|
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
|
||||||
print_tree(node['left'], depth+1)
|
|
||||||
print_tree(node['right'], depth+1)
|
|
||||||
else:
|
|
||||||
print('%s[%s]' % ((depth*' ', node)))
|
|
||||||
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
tree = build_tree(dataset, 5, 0)
|
|
||||||
print_tree(tree)
|
|
|
@ -1,92 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
|
||||||
outcomes = [row[-1] for row in group]
|
|
||||||
return max(set(outcomes), key=outcomes.count)
|
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
|
||||||
left, right = node['groups']
|
|
||||||
del(node['groups'])
|
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
|
||||||
return
|
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
|
||||||
return
|
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
|
||||||
node['left'] = to_terminal(left)
|
|
||||||
else:
|
|
||||||
node['left'] = get_split(left)
|
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
|
||||||
node['right'] = to_terminal(right)
|
|
||||||
else:
|
|
||||||
node['right'] = get_split(right)
|
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
|
||||||
root = get_split(train)
|
|
||||||
split(root, max_depth, min_size, 1)
|
|
||||||
return root
|
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
|
||||||
if isinstance(node, dict):
|
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
|
||||||
print_tree(node['left'], depth+1)
|
|
||||||
print_tree(node['right'], depth+1)
|
|
||||||
else:
|
|
||||||
print('%s[%s]' % ((depth*' ', node)))
|
|
||||||
|
|
||||||
|
|
||||||
if __name__ == "__main__":
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
tree = build_tree(dataset, 5, 0)
|
|
||||||
print_tree(tree)
|
|
|
@ -1,92 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
|
||||||
outcomes = [row[-1] for row in group]
|
|
||||||
return max(set(outcomes), key=outcomes.count)
|
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
|
||||||
left, right = node['groups']
|
|
||||||
del(node['groups'])
|
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
|
||||||
return
|
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
|
||||||
return
|
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
|
||||||
node['left'] = to_terminal(left)
|
|
||||||
else:
|
|
||||||
node['left'] = get_split(left)
|
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
|
||||||
node['right'] = to_terminal(right)
|
|
||||||
else:
|
|
||||||
node['right'] = get_split(right)
|
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
|
||||||
root = get_split(train)
|
|
||||||
split(root, max_depth, min_size, 1)
|
|
||||||
return root
|
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
|
||||||
if isinstance(node, dict):
|
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
|
||||||
print_tree(node['left'], depth+1)
|
|
||||||
print_tree(node['right'], depth+1)
|
|
||||||
else:
|
|
||||||
print('%s[%s]' % ((depth*' ', node)))
|
|
||||||
|
|
||||||
|
|
||||||
if __name__ == "__main__":
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
tree = build_tree(dataset, 1, 1)
|
|
||||||
print_tree(tree)
|
|
|
@ -1,92 +0,0 @@
|
||||||
import pandas as pd
|
|
||||||
def test_split(index, value, dataset):
|
|
||||||
left, right = list(), list()
|
|
||||||
for row in dataset:
|
|
||||||
if row[index] < value:
|
|
||||||
left.append(row)
|
|
||||||
else:
|
|
||||||
right.append(row)
|
|
||||||
return left, right
|
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
|
||||||
for group in groups:
|
|
||||||
size = float(len(group))
|
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
|
||||||
continue
|
|
||||||
score = 0.0
|
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
|
||||||
score += p * p
|
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
|
||||||
return gini
|
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
|
||||||
for index in range(len(dataset[0])-1):
|
|
||||||
for row in dataset:
|
|
||||||
groups = test_split(index, row[index], dataset)
|
|
||||||
gini = gini_index(groups, class_values)
|
|
||||||
if gini < b_score:
|
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
|
||||||
outcomes = [row[-1] for row in group]
|
|
||||||
return max(set(outcomes), key=outcomes.count)
|
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
|
||||||
left, right = node['groups']
|
|
||||||
del(node['groups'])
|
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
|
||||||
return
|
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
|
||||||
return
|
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
|
||||||
node['left'] = to_terminal(left)
|
|
||||||
else:
|
|
||||||
node['left'] = get_split(left)
|
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
|
||||||
node['right'] = to_terminal(right)
|
|
||||||
else:
|
|
||||||
node['right'] = get_split(right)
|
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
|
||||||
root = get_split(train)
|
|
||||||
split(root, max_depth, min_size, 1)
|
|
||||||
return root
|
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
|
||||||
if isinstance(node, dict):
|
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
|
||||||
print_tree(node['left'], depth+1)
|
|
||||||
print_tree(node['right'], depth+1)
|
|
||||||
else:
|
|
||||||
print('%s[%s]' % ((depth*' ', node)))
|
|
||||||
|
|
||||||
|
|
||||||
if __name__ == "__main__":
|
|
||||||
dataset = pd.read_excel('Train.xlsx', sheet_name="Sheet1").to_numpy()
|
|
||||||
tree = build_tree(dataset, 1, 1)
|
|
||||||
print_tree(tree)
|
|
|
@ -1,15 +0,0 @@
|
||||||
{
|
|
||||||
// Use IntelliSense to learn about possible attributes.
|
|
||||||
// Hover to view descriptions of existing attributes.
|
|
||||||
// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
|
|
||||||
"version": "0.2.0",
|
|
||||||
"configurations": [
|
|
||||||
{
|
|
||||||
"name": "Python: Current File",
|
|
||||||
"type": "python",
|
|
||||||
"request": "launch",
|
|
||||||
"program": "${file}",
|
|
||||||
"console": "integratedTerminal"
|
|
||||||
}
|
|
||||||
]
|
|
||||||
}
|
|
|
@ -1,3 +0,0 @@
|
||||||
{
|
|
||||||
"python.pythonPath": "C:\\Users\\user\\AppData\\Local\\Programs\\Python\\Python38-32\\python.exe"
|
|
||||||
}
|
|
30
gini.py
30
gini.py
|
@ -8,27 +8,27 @@ def test_split(index, value, dataset):
|
||||||
right.append(row)
|
right.append(row)
|
||||||
return left, right
|
return left, right
|
||||||
|
|
||||||
# Calculate the Gini index for a split dataset
|
|
||||||
def gini_index(groups, classes):
|
def gini_index(groups, classes):
|
||||||
# count all samples at split point
|
|
||||||
n_instances = float(sum([len(group) for group in groups]))
|
n_instances = float(sum([len(group) for group in groups]))
|
||||||
# sum weighted Gini index for each group
|
|
||||||
gini = 0.0
|
gini = 0.0
|
||||||
for group in groups:
|
for group in groups:
|
||||||
size = float(len(group))
|
size = float(len(group))
|
||||||
# avoid divide by zero
|
|
||||||
if size == 0:
|
if size == 0:
|
||||||
continue
|
continue
|
||||||
score = 0.0
|
score = 0.0
|
||||||
# score the group based on the score for each class
|
|
||||||
for class_val in classes:
|
for class_val in classes:
|
||||||
p = [row[-1] for row in group].count(class_val) / size
|
p = [row[-1] for row in group].count(class_val) / size
|
||||||
score += p * p
|
score += p * p
|
||||||
# weight the group score by its relative size
|
|
||||||
gini += (1.0 - score) * (size / n_instances)
|
gini += (1.0 - score) * (size / n_instances)
|
||||||
return gini
|
return gini
|
||||||
|
|
||||||
# Select the best split point for a dataset
|
|
||||||
def get_split(dataset):
|
def get_split(dataset):
|
||||||
class_values = list(set(row[-1] for row in dataset))
|
class_values = list(set(row[-1] for row in dataset))
|
||||||
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
b_index, b_value, b_score, b_groups = 999, 999, 999, None
|
||||||
|
@ -40,43 +40,43 @@ def get_split(dataset):
|
||||||
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
b_index, b_value, b_score, b_groups = index, row[index], gini, groups
|
||||||
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
return {'index':b_index, 'value':b_value, 'groups':b_groups}
|
||||||
|
|
||||||
# Create a terminal node value
|
|
||||||
def to_terminal(group):
|
def to_terminal(group):
|
||||||
outcomes = [row[-1] for row in group]
|
outcomes = [row[-1] for row in group]
|
||||||
return max(set(outcomes), key=outcomes.count)
|
return max(set(outcomes), key=outcomes.count)
|
||||||
|
|
||||||
# Create child splits for a node or make terminal
|
|
||||||
def split(node, max_depth, min_size, depth):
|
def split(node, max_depth, min_size, depth):
|
||||||
left, right = node['groups']
|
left, right = node['groups']
|
||||||
del(node['groups'])
|
del(node['groups'])
|
||||||
# check for a no split
|
|
||||||
if not left or not right:
|
if not left or not right:
|
||||||
node['left'] = node['right'] = to_terminal(left + right)
|
node['left'] = node['right'] = to_terminal(left + right)
|
||||||
return
|
return
|
||||||
# check for max depth
|
|
||||||
if depth >= max_depth:
|
if depth >= max_depth:
|
||||||
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
node['left'], node['right'] = to_terminal(left), to_terminal(right)
|
||||||
return
|
return
|
||||||
# process left child
|
|
||||||
if len(left) <= min_size:
|
if len(left) <= min_size:
|
||||||
node['left'] = to_terminal(left)
|
node['left'] = to_terminal(left)
|
||||||
else:
|
else:
|
||||||
node['left'] = get_split(left)
|
node['left'] = get_split(left)
|
||||||
split(node['left'], max_depth, min_size, depth+1)
|
split(node['left'], max_depth, min_size, depth+1)
|
||||||
# process right child
|
|
||||||
if len(right) <= min_size:
|
if len(right) <= min_size:
|
||||||
node['right'] = to_terminal(right)
|
node['right'] = to_terminal(right)
|
||||||
else:
|
else:
|
||||||
node['right'] = get_split(right)
|
node['right'] = get_split(right)
|
||||||
split(node['right'], max_depth, min_size, depth+1)
|
split(node['right'], max_depth, min_size, depth+1)
|
||||||
|
|
||||||
# Build a decision tree
|
|
||||||
def build_tree(train, max_depth, min_size):
|
def build_tree(train, max_depth, min_size):
|
||||||
root = get_split(train)
|
root = get_split(train)
|
||||||
split(root, max_depth, min_size, 1)
|
split(root, max_depth, min_size, 1)
|
||||||
return root
|
return root
|
||||||
|
|
||||||
# Print a decision tree
|
|
||||||
def print_tree(node, depth=0):
|
def print_tree(node, depth=0):
|
||||||
if isinstance(node, dict):
|
if isinstance(node, dict):
|
||||||
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
print('%s[X%d < %.3f]' % ((depth*' ', (node['index']+1), node['value'])))
|
||||||
|
|
Loading…
Reference in New Issue