Merge branch 'new_fft' into 'NIFTy_5'

Adjust to new pocketfft interface

See merge request !329

nifty5/fft.py

@@ -15,8 +15,6 @@
 #
 # NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik.
 
-from .utilities import iscomplextype
-import numpy as np
 import pypocketfft
 
 _nthreads = 1
@@ -31,81 +29,14 @@ def set_nthreads(nthr):
     _nthreads = nthr
 
 
-# FIXME this should not be necessary ... no one should call a complex FFT
-# with a float array.
-def _make_complex(a):
-    if a.dtype in (np.complex64, np.complex128):
-        return a
-    if a.dtype == np.float64:
-        return a.astype(np.complex128)
-    if a.dtype == np.float32:
-        return a.astype(np.complex64)
-    raise NotImplementedError
-
-
 def fftn(a, axes=None):
-    return pypocketfft.fftn(_make_complex(a), axes=axes, nthreads=_nthreads)
-
-
-def rfftn(a, axes=None):
-    return pypocketfft.rfftn(a, axes=axes, nthreads=_nthreads)
+    return pypocketfft.c2c(a, axes=axes, nthreads=_nthreads)
 
 
 def ifftn(a, axes=None):
-    # FIXME this is a temporary fix and can be done more elegantly
-    if axes is None:
-        fct = 1./a.size
-    else:
-        fct = 1./np.prod(np.take(a.shape, axes))
-    return pypocketfft.ifftn(_make_complex(a), axes=axes, fct=fct,
-                             nthreads=_nthreads)
+    return pypocketfft.c2c(a, axes=axes, inorm=2, forward=False,
+                           nthreads=_nthreads)
 
 
 def hartley(a, axes=None):
-    return pypocketfft.hartley2(a, axes=axes, nthreads=_nthreads)
-
-
-# Do a real-to-complex forward FFT and return the _full_ output array
-def my_fftn_r2c(a, axes=None):
-    # Check if the axes provided are valid given the shape
-    if axes is not None and \
-            not all(axis < len(a.shape) for axis in axes):
-        raise ValueError("Provided axes do not match array shape")
-    if iscomplextype(a.dtype):
-        raise TypeError("Transform requires real-valued input arrays.")
-
-    tmp = rfftn(a, axes=axes)
-
-    def _fill_complex_array(tmp, res, axes):
-        if axes is None:
-            axes = tuple(range(tmp.ndim))
-        lastaxis = axes[-1]
-        ntmplast = tmp.shape[lastaxis]
-        slice1 = [slice(None)]*lastaxis + [slice(0, ntmplast)]
-        res[tuple(slice1)] = tmp
-
-        def _fill_upper_half_complex(tmp, res, axes):
-            lastaxis = axes[-1]
-            nlast = res.shape[lastaxis]
-            ntmplast = tmp.shape[lastaxis]
-            nrem = nlast - ntmplast
-            slice1 = [slice(None)]*lastaxis + [slice(ntmplast, None)]
-            slice2 = [slice(None)]*lastaxis + [slice(nrem, 0, -1)]
-            for i in axes[:-1]:
-                slice1[i] = slice(1, None)
-                slice2[i] = slice(None, 0, -1)
-            # np.conjugate(tmp[slice2], out=res[slice1])
-            res[tuple(slice1)] = np.conjugate(tmp[tuple(slice2)])
-            for i, ax in enumerate(axes[:-1]):
-                dim1 = tuple([slice(None)]*ax + [slice(0, 1)])
-                axes2 = axes[:i] + axes[i+1:]
-                _fill_upper_half_complex(tmp[dim1], res[dim1], axes2)
-
-        _fill_upper_half_complex(tmp, res, axes)
-        return res
-
-    return _fill_complex_array(tmp, np.empty_like(a, dtype=tmp.dtype), axes)
-
-
-def my_fftn(a, axes=None):
-    return fftn(a, axes=axes)
+    return pypocketfft.genuine_hartley(a, axes=axes, nthreads=_nthreads)

nifty5/operators/harmonic_operators.py

@@ -202,7 +202,7 @@ class HartleyOperator(LinearOperator):
             rem_axes = tuple(i for i in axes if i != oldax)
             tmp = x.val
             ldat = dobj.local_data(tmp)
-            ldat = fft.my_fftn_r2c(ldat, axes=rem_axes)
+            ldat = fft.fftn(ldat, axes=rem_axes)
             if oldax != 0:
                 raise ValueError("bad distribution")
             ldat2 = ldat.reshape((ldat.shape[0],
@@ -211,7 +211,7 @@ class HartleyOperator(LinearOperator):
             tmp = dobj.from_local_data(shp2d, ldat2, distaxis=0)
             tmp = dobj.transpose(tmp)
             ldat2 = dobj.local_data(tmp)
-            ldat2 = fft.my_fftn(ldat2, axes=(1,))
+            ldat2 = fft.fftn(ldat2, axes=(1,))
             ldat2 = ldat2.real+ldat2.imag
             tmp = dobj.from_local_data(tmp.shape, ldat2, distaxis=0)
             tmp = dobj.transpose(tmp)