code: def _add_at(add_at, x, row, col, data):
      assert data.size > 0
      last_nz = data.size - (data != 0)[::-1].argmax()
      add_at(x, (row[:last_nz], col[:last_nz]), data[:last_nz])
  
file_path: chainer/chainer/utils/sparse.py
imports: import numpy
  import chainer
  from chainer import backend
  from chainer import cuda
label_desc: Use image node_id 1 for calling a global function with example usage: _add_at(add_at, x, row, col, data) without return types