void fftscale2(unsigned int N, const long dimensions[N], unsigned long flags, const long ostrides[N], complex float* dst, const long istrides[N], const complex float* src)
{
long fft_dims[N];
md_select_dims(N, flags, fft_dims, dimensions);
float scale = 1. / sqrtf((float)md_calc_size(N, fft_dims));
md_zsmul2(N, dimensions, ostrides, dst, istrides, src, scale);
}
static void fftmod2_r(unsigned int N, const long dims[N], unsigned long flags, const long ostrs[N], complex float* dst, const long istrs[N], const complex float* src, bool inv, double phase)
{
if (0 == flags) {
md_zsmul2(N, dims, ostrs, dst, istrs, src, cexp(M_PI * 2.i * (inv ? -phase : phase)));
return;
}
/* this will also currently be slow on the GPU because we do not
* support strides there on the lowest level */
unsigned int i = N - 1;
while (!MD_IS_SET(flags, i))
i--;
#if 1
// If there is only one dimensions left and it is the innermost
// which is contiguous optimize using md_zfftmod2
if ((0u == MD_CLEAR(flags, i)) && (1 == md_calc_size(i, dims))
&& (CFL_SIZE == ostrs[i]) && (CFL_SIZE == istrs[i])) {
md_zfftmod2(N - i, dims + i, ostrs + i, dst, istrs + i, src, inv, phase);
return;
}
#endif
long tdims[N];
md_select_dims(N, ~MD_BIT(i), tdims, dims);
#pragma omp parallel for
for (int j = 0; j < dims[i]; j++)
fftmod2_r(N, tdims, MD_CLEAR(flags, i),
ostrs, (void*)dst + j * ostrs[i], istrs, (void*)src + j * istrs[i],
inv, phase + fftmod_phase(dims[i], j));
}
// y = 2*x - circshift(x,center_adj) - circshift(x,center)
static void zfinitediff_normal(const linop_data_t* _data,
complex float* optr, const complex float* iptr)
{
const auto data = CAST_DOWN(zfinitediff_data, _data);
// Turns out that this is faster, but this requires extra memory.
complex float* tmp = md_alloc_sameplace(data->D, data->dims_in, CFL_SIZE, iptr);
zfinitediff_apply(_data, tmp, iptr);
zfinitediff_adjoint(_data, optr, tmp);
md_free(tmp);
return; // FIXME: WTF?
unsigned long d = data->dim_diff;
long nx = data->dims_in[d];
long offset;
long dims_sub[data->D];
md_copy_dims(data->D, dims_sub, data->dims_in);
// optr and iptr same size regardless if do_circdiff true/false
// if (data->do_circdiff)
// out = 2*in;
// out(..,1:(end-1),..) = out(..,1:(end-1),..) - in(..,2:end,..)
// out(..,2:end,..) = out(..,2:end,..) - in(..,1:(end-1),..)
// out(..,end,..) = out(..,end,..) - in(..,1,..)
// out(..,1,..) = out(..,1,..) - in(..,end,..)
//
// else
// out(..,1,..) = in(..,1,..)
// out(..,end,..) = in(..,end,..)
// out(..,2:(end-1),..) = 2*in(..,2:(end-1),..)
// out(..,1:(end-1),..) = out(..,1:(end-1),..) - in(..,2:end,..)
// out(..,2:end,..) = out(..,2:end,..) - in(..,1:(end-1),..)
//
if (data->do_circdiff) {
md_zsmul2(data->D, data->dims_in, data->strides_in, optr,
data->strides_in, iptr, 2.);
dims_sub[d] = (nx - 1);
offset = data->strides_in[d] / CFL_SIZE;
// out(..,1:(end-1),..) = out(..,1:(end-1),..) - in(..,2:end,..)
md_zsub2(data->D, dims_sub, data->strides_in, optr,
data->strides_in, optr, data->strides_in, iptr + offset);
// out(..,2:end,..) = out(..,2:end,..) - in(..,1:(end-1),..)
md_zsub2(data->D, dims_sub, data->strides_in, optr + offset,
data->strides_in, optr + offset, data->strides_in, iptr);
dims_sub[d] = 1;
offset = (nx - 1) * data->strides_in[d] / CFL_SIZE;
// out(..,1,..) = out(..,1,..) - in(..,end,..)
md_zsub2(data->D, dims_sub, data->strides_in, optr,
data->strides_in, optr, data->strides_in, iptr + offset);
// out(..,end,..) = out(..,end,..) - in(..,1,..)
md_zsub2(data->D, dims_sub, data->strides_in, optr+offset,
data->strides_in, optr+offset, data->strides_in, iptr);
} else {
dims_sub[d] = 1;
offset = (nx - 1) * data->strides_in[d] / CFL_SIZE;
// out(..,1,..) = in(..,1,..)
md_copy2(data->D, dims_sub,
data->strides_in, optr, data->strides_in, iptr, CFL_SIZE);
// out(..,end,..) = in(..,end,..)
md_copy2(data->D, dims_sub,
data->strides_in, optr + offset, data->strides_in, iptr + offset,
CFL_SIZE);
dims_sub[d] = nx - 2;
offset = data->strides_in[d] / CFL_SIZE;
// out(..,2:(end-1),..) = 2*in(..,2:(end-1),..)
md_zsmul2(data->D, dims_sub, data->strides_in, optr + offset,
data->strides_in, iptr + offset, 2.);
dims_sub[d] = nx - 1;
offset = data->strides_in[d] / CFL_SIZE;
// out(..,1:(end-1),..) = out(..,1:(end-1),..) - in(..,2:end,..)
md_zsub2(data->D, dims_sub, data->strides_in, optr,
data->strides_in, optr, data->strides_in, iptr + offset);
// out(..,2:end,..) = out(..,2:end,..) - in(..,1:(end-1),..)
md_zsub2(data->D, dims_sub, data->strides_in, optr + offset,
data->strides_in, optr + offset, data->strides_in, iptr);
}
}
