cSTIR_PLSPriorGradient has confusing name

[KrisThielemans]

SIRF/src/xSTIR/cSTIR/cstir.cpp

Lines 1262 to 1263 in 2c66faf

	PLSPrior<float>& prior = objectFromHandle<PLSPrior<float> >(ptr_p);
	auto sptr_im = prior.get_anatomical_grad_sptr(dir);

computes the "image gradient" of the anatomical image, not the gradient of the prior w.r.t. the argument.

The python implementation should just call cSTIR_priorGradient, like for all other priors.

[evgueni-ovtchinnikov]

PLSPrior inherits method get_gradient (and its alias gradient) from Prior.

cSTIR_PLSPriorGradient is called from PLSPrior.get_anatomical_grad (and essentially wraps stir::PLSPrior.get_anatomical_grad_sptr()) - should I perhaps just rename the former to cSTIR_PLSPriorAnatomicalGrad to avoid confusion?

[KrisThielemans]

ah. great. yes, I think a rename will help. Therefore not urgent.

[evgueni-ovtchinnikov]

taken care of by recently merged PR #1246