Sum of the values in a tensor, alongside the specified axis.

`k_sum(x, axis = NULL, keepdims = FALSE)`

A tensor with sum of `x`

.

- x
A tensor or variable.

- axis
An integer, the axis to sum over (axis indexes are 1-based).

- keepdims
A boolean, whether to keep the dimensions or not. If

`keepdims`

is`FALSE`

, the rank of the tensor is reduced by 1. If`keepdims`

is`TRUE`

, the reduced dimension is retained with length 1.

This function is part of a set of Keras backend functions that enable lower level access to the core operations of the backend tensor engine (e.g. TensorFlow, CNTK, Theano, etc.).

You can see a list of all available backend functions here: https://tensorflow.rstudio.com/reference/keras/index.html#backend.