code: def calc_dotproduct_idx(
      dotproduct, m, mp, idx, sigmax, idx_nn, meanx
  ):
      dotproduct[idx] = (m - mp[idx] ** 2 / 2) * sigmax[idx] * sigmax[
          idx_nn
      ] + m * meanx[idx] * meanx[idx_nn]
  
      return dotproduct
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from __future__ import unicode_literals
  import math
  import time
  import warnings
  import numpy
label_desc: Use image node_id 12 for calling a global function with example usage: calc_dotproduct_idx(dotproduct, m, mp, idx, sigmax, idx_nn, meanx) and returns: dotproduct