larray.Array.cumsum

Array.cumsum(axis=-1) → Union[Array, bool, int, float, str, bytes, generic][source]

Return the cumulative sum of array elements along an axis.

Parameters

axisint or str or Axis, optional: Axis along which to perform the cumulative sum. If given as position, it can be a negative integer, in which case it counts from the last to the first axis. By default, the cumulative sum is performed along the last axis.

Returns

Array or scalar

See also

Array.cumprod, Array.sum, Array.sum_by
Array.prod, Array.prod_by

Notes

Cumulative aggregation functions accept only one axis

Examples

>>> arr = ndtest((4, 4))
>>> arr
a\b  b0  b1  b2  b3
 a0   0   1   2   3
 a1   4   5   6   7
 a2   8   9  10  11
 a3  12  13  14  15
>>> arr.cumsum()
a\b  b0  b1  b2  b3
 a0   0   1   3   6
 a1   4   9  15  22
 a2   8  17  27  38
 a3  12  25  39  54
>>> arr.cumsum('a')
a\b  b0  b1  b2  b3
 a0   0   1   2   3
 a1   4   6   8  10
 a2  12  15  18  21
 a3  24  28  32  36