multiresolution_sub​tract.m

Subtracts vectors @ different resolution.

This function will subtract two vectors x and y at different resolutions x_grid and y_grid and give an output at the lower resolution. Either x or y may be the low-resolution vector. Vectors may be unsorted according to x_grid and y_grid, but they will be sorted using sort_by_x.m.

Function operates very fast with decent accuracy, but has option to operate slowly at increased accuracy.