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
```