def impl(data, wavelet, mode, axis):
coeff_len = dwt_coeff_length(
data.shape[axis], len(
wavelet.dec_hi), mode)
out_shape = tuple_setitem(data.shape, axis, coeff_len)
if axis < 0 or axis >= data.ndim:
raise ValueError("0 <= axis < data.ndim failed")
ca = np.empty(out_shape, dtype=data.dtype)
cd = np.empty(out_shape, dtype=data.dtype)
# Iterate over all points except along the slicing axis
for idx in np.ndindex(*tuple_setitem(data.shape, axis, 1)):
initial_in_row = slice_axis(data, idx, axis, None)
initial_ca_row = slice_axis(ca, idx, axis, None)
initial_cd_row = slice_axis(cd, idx, axis, None)
# The numba array type returned by slice_axis assumes
# non-contiguity in the general case.
# However, the slice may actually be contiguous in layout
# If so, cast the array type to obtain type contiguity
# else, copy the slice to obtain contiguity in
# both type and layout
if initial_in_row.flags.c_contiguous:
in_row = force_type_contiguity(initial_in_row)
else:
in_row = initial_in_row.copy()
if initial_ca_row.flags.c_contiguous:
ca_row = force_type_contiguity(initial_ca_row)
else:
ca_row = initial_ca_row.copy()
if initial_cd_row.flags.c_contiguous:
cd_row = force_type_contiguity(initial_cd_row)
else:
cd_row = initial_cd_row.copy()
# Compute the approximation and detail coefficients
downsampling_convolution(in_row, ca_row, wavelet.dec_lo, mode, 2)
downsampling_convolution(in_row, cd_row, wavelet.dec_hi, mode, 2)
# If necessary, copy back into the output
if not initial_ca_row.flags.c_contiguous:
initial_ca_row[:] = ca_row[:]
if not initial_cd_row.flags.c_contiguous:
initial_cd_row[:] = cd_row[:]
return ca, cd
def fn(A):
for axis in range(A.ndim):
for i in np.ndindex(*tuple_setitem(A.shape, axis, 1)):
S = slice_axis(A, i, axis, None)
if S.flags.c_contiguous != (S.itemsize == S.strides[0]):
raise ValueError("contiguity flag doesn't match layout")
def impl(approx_coeffs, detail_coeffs,
wavelet, mode, axis):
if have_approx and have_detail:
coeff_shape = approx_coeffs.shape
it = enumerate(zip(approx_coeffs.shape, detail_coeffs.shape))
# NOTE(sjperkins)
# Clip the coefficient dimensions to the smallest dimensions
# pywt clips in waverecn and fails in idwt and idwt_axis
# on heterogenous coefficient shapes.
# The actual clipping is performed in slice_axis
for i, (asize, dsize) in it:
size = asize if asize < dsize else dsize
coeff_shape = tuple_setitem(coeff_shape, i, size)
elif have_approx:
coeff_shape = approx_coeffs.shape
elif have_detail:
coeff_shape = detail_coeffs.shape
else:
raise ValueError("Either approximation or detail must be present")
if not (0 <= axis < len(coeff_shape)):
raise ValueError(("0 <= axis < coeff.ndim does not hold"))
idwt_len = idwt_buffer_length(coeff_shape[axis],
wavelet.rec_lo.shape[0],
mode)
out_shape = tuple_setitem(coeff_shape, axis, idwt_len)
output = np.empty(out_shape, dtype=out_dtype)
# Iterate over all points except along the slicing axis
for idx in np.ndindex(*tuple_setitem(output.shape, axis, 1)):
initial_out_row = slice_axis(output, idx, axis, None)
# Zero if we have a contiguous slice, else allocate
if initial_out_row.flags.c_contiguous:
out_row = force_type_contiguity(initial_out_row)
out_row[:] = 0
else:
out_row = np.zeros_like(initial_out_row)
# Apply approximation coefficients if they exist
if approx_coeffs is not None:
initial_ca_row = slice_axis(approx_coeffs, idx,
axis, coeff_shape[axis])
if initial_ca_row.flags.c_contiguous:
ca_row = force_type_contiguity(initial_ca_row)
else:
ca_row = initial_ca_row.copy()
upsampling_convolution_valid_sf(ca_row, wavelet.rec_lo,
out_row, mode)
# Apply detail coefficients if they exist
if detail_coeffs is not None:
initial_cd_row = slice_axis(detail_coeffs, idx,
axis, coeff_shape[axis])
if initial_cd_row.flags.c_contiguous:
cd_row = force_type_contiguity(initial_cd_row)
else:
cd_row = initial_cd_row.copy()
upsampling_convolution_valid_sf(cd_row, wavelet.rec_hi,
out_row, mode)
# Copy back output row if the output space was non-contiguous
if not initial_out_row.flags.c_contiguous:
initial_out_row[:] = out_row
return output
def fn(a, index, axis=1, extent=None):
return slice_axis(a, index, axis, extent)