segment_sum(data, segment_ids, num_segments=None, indices_are_sorted=False, unique_indices=False, bucket_size=None)¶
Computes the sum within segments of an array.
Similar to TensorFlow’s segment_sum: https://www.tensorflow.org/api_docs/python/tf/math/segment_sum
data – an array with the values to be summed.
segment_ids – an array with integer dtype that indicates the segments of data (along its leading axis) to be summed. Values can be repeated and need not be sorted. Values outside of the range [0, num_segments) are dropped and do not contribute to the sum.
num_segments – optional, an int with nonnegative value indicating the number of segments. The default is set to be the minimum number of segments that would support all indices in
segment_ids, calculated as
max(segment_ids) + 1. Since num_segments determines the size of the output, a static value must be provided to use
indices_are_sorted – whether
segment_idsis known to be sorted.
unique_indices – whether segment_ids is known to be free of duplicates.
bucket_size – size of bucket to group indices into.
segment_sumis performed on each bucket separately to improve numerical stability of addition. Default
Nonemeans no bucketing.
An array with shape
(num_segments,) + data.shape[1:]representing the segment sums.