Computation of the derivative of the Loss ( WBarycenter(Dictionary,lambda), q)
These matlab functions were used to produce figure 11 in the following SIGGRAPH paper.
http://liris.cnrs.fr/~nbonneel/WassersteinBarycentricCoordinates/
In that experiment, we project a brain (3d tensor of ~200^3 voxels) onto a set of 14 brains in the Wasserstein sense.
That computation can be carried out by parallelizing computations of several GPUs. This is what the function
computeBarycenterDerivativeMultiGPU.m
in this package does.