def _ifft_positive(data):
if data.dtype == typequaternion:
fr = get_component(data, "R")
dr = np.fft.fft(np.fft.ifftshift(fr, -1)) * data.shape[-1]
fi = get_component(data, "I")
di = np.fft.fft(np.fft.ifftshift(fi, -1)) * data.shape[-1]
# rebuild the quaternion
data = as_quaternion(dr, di)
else:
data = np.fft.fft(np.fft.ifftshift(data, -1)) * data.shape[-1]
return data
def _ifft(data):
if data.dtype == typequaternion:
fr = get_component(data, "R")
dr = np.fft.ifft(np.fft.ifftshift(fr, -1))
fi = get_component(data, "I")
di = np.fft.ifft(np.fft.ifftshift(fi, -1))
# rebuild the quaternion
data = as_quaternion(dr, di)
else:
data = np.fft.ifft(np.fft.ifftshift(data, -1))
return data
def _fft(data):
if data.dtype == typequaternion:
dr = get_component(data, "R")
fr = np.fft.fftshift(np.fft.fft(dr), -1)
di = get_component(data, "I")
fi = np.fft.fftshift(np.fft.fft(di), -1)
# rebuild the quaternion
data = as_quaternion(fr, fi)
else:
data = np.fft.fftshift(np.fft.fft(data), -1)
return data
def _fft_positive(data):
if data.dtype == typequaternion:
dr = get_component(data, "R")
fr = np.fft.fftshift(np.fft.ifft(dr).astype(
data.dtype)) * data.shape[-1]
di = get_component(data, "I")
fi = np.fft.fftshift(np.fft.ifft(di).astype(
data.dtype)) * data.shape[-1]
# rebuild the quaternion
data = as_quaternion(fr, fi)
else:
data = np.fft.fftshift(np.fft.ifft(data).astype(
data.dtype)) * data.shape[-1]
return data
def component(self, select="REAL"):
"""
Take selected components of an hypercomplex array (RRR, RIR, ...).
Parameters
----------
select : str, optional, default='REAL'
If 'REAL', only real component in all dimensions will be selected.
ELse a string must specify which real (R) or imaginary (I) component
has to be selected along a specific dimension. For instance,
a string such as 'RRI' for a 2D hypercomplex array indicated
that we take the real component in each dimension except the last
one, for which imaginary component is preferred.
Returns
-------
component
Component of the complex or hypercomplex array.
"""
if not select:
# no selection - returns inchanged
return self
new = self.copy()
ma = self.masked_data
ma = get_component(ma, select)
if isinstance(ma, np.ma.masked_array):
new._data = ma.data
new._mask = ma.mask
else:
new._data = ma
if hasattr(ma, "mask"):
new._mask = ma.mask
else:
new._mask = NOMASK
return new