Inherits Operation.
Builds a 3D histogram grid 'Result R' from an input 2D grid layer 'Grid A'. The extra dimension (z) in the output grid are the histogram bins. The number and spacing of the bins are set using 'Number of bins' and 'Bin spacing', respectively. This function is designed to be called multiple times with different values of 'Grid A', building up the resulting histogram. The histogram is constructed by incrementing the appropriate bin in 'Result R' each time the operation is executed.