Source code for featuretools.primitives.standard.aggregation.max_consecutive_false

from woodwork.column_schema import ColumnSchema
from woodwork.logical_types import Boolean, Integer

from featuretools.primitives.base import AggregationPrimitive

[docs]class MaxConsecutiveFalse(AggregationPrimitive): """Determines the maximum number of consecutive False values in the input Examples: >>> max_consecutive_false = MaxConsecutiveFalse() >>> max_consecutive_false([True, False, False, True, True, False]) 2 """ name = "max_consecutive_false" input_types = [ColumnSchema(logical_type=Boolean)] return_type = ColumnSchema(logical_type=Integer, semantic_tags={"numeric"}) stack_on_self = False default_value = 0 def get_function(self): def max_consecutive_false(x): # invert the input array to work properly with the computation x[x.notnull()] = ~(x[x.notnull()].astype(bool)) # find the locations where the value changes from the previous value not_equal = x != x.shift() # Use cumulative sum to determine where consecutive values occur. When the # sum changes, consecutive False values are present, when the cumulative # sum remains unchnaged, consecutive True values are present. not_equal_sum = not_equal.cumsum() # group the input by the cumulative sum values and use cumulative count # to count the number of consecutive values. Add 1 to account for the cumulative # sum starting at zero where the first True occurs consecutive = x.groupby(not_equal_sum).cumcount() + 1 # multiply by the inverted input to keep only the counts that correspond to # false values consecutive_false = consecutive * x # return the max of all the consecutive false values return consecutive_false.max() return max_consecutive_false