diff --git a/transformations/gllmtransformation.py b/transformations/gllmtransformation.py
index 283e869e8a32df416e8e20cea6cdff882a6436a2..8ec541fc6ce6a5a2ab16642715c2948be762a699 100644
--- a/transformations/gllmtransformation.py
+++ b/transformations/gllmtransformation.py
@@ -9,7 +9,7 @@ gl = gdi.get('libsharp_wrapper_gl')
class GLLMTransformation(Transformation):
- def __init__(self, domain, codomain, module=None):
+ def __init__(self, domain, codomain=None, module=None):
if 'libsharp_wrapper_gl' not in gdi:
raise ImportError("The module libsharp is needed but not available")
@@ -19,6 +19,36 @@ class GLLMTransformation(Transformation):
else:
raise ValueError("ERROR: Incompatible codomain!")
+ @staticmethod
+ def get_codomain(domain):
+ """
+ Generates a compatible codomain to which transformations are
+ reasonable, i.e.\ an instance of the :py:class:`lm_space` class.
+
+ Parameters
+ ----------
+ domain: GLSpace
+ Space for which a codomain is to be generated
+
+ Returns
+ -------
+ codomain : LMSpace
+ A compatible codomain.
+ """
+ if domain is None:
+ raise ValueError('ERROR: cannot generate codomain for None')
+
+ if not isinstance(domain, GLSpace):
+ raise TypeError('ERROR: domain needs to be a GLSpace')
+
+ nlat = domain.paradict['nlat']
+ lmax = nlat - 1
+ mmax = nlat - 1
+ if domain.dtype == np.dtype('float32'):
+ return LMSpace(lmax=lmax, mmax=mmax, dtype=np.complex64)
+ else:
+ return LMSpace(lmax=lmax, mmax=mmax, dtype=np.complex128)
+
@staticmethod
def check_codomain(domain, codomain):
if not isinstance(domain, GLSpace):
diff --git a/transformations/hplmtransformation.py b/transformations/hplmtransformation.py
index de2c445bc082ca756bd78797b8feaaafb396b413..557f1b7bb4f424931fab57d6f54fd0b7c7e9465d 100644
--- a/transformations/hplmtransformation.py
+++ b/transformations/hplmtransformation.py
@@ -9,7 +9,7 @@ hp = gdi.get('healpy')
class HPLMTransformation(Transformation):
- def __init__(self, domain, codomain, module=None):
+ def __init__(self, domain, codomain=None, module=None):
if 'healpy' not in gdi:
raise ImportError("The module healpy is needed but not available")
@@ -19,6 +19,32 @@ class HPLMTransformation(Transformation):
else:
raise ValueError("ERROR: Incompatible codomain!")
+ @staticmethod
+ def get_codomain(domain):
+ """
+ Generates a compatible codomain to which transformations are
+ reasonable, i.e.\ an instance of the :py:class:`lm_space` class.
+
+ Parameters
+ ----------
+ domain: HPSpace
+ Space for which a codomain is to be generated
+
+ Returns
+ -------
+ codomain : LMSpace
+ A compatible codomain.
+ """
+ if domain is None:
+ raise ValueError('ERROR: cannot generate codomain for None')
+
+ if not isinstance(domain, HPSpace):
+ raise TypeError('ERROR: domain needs to be a HPSpace')
+
+ lmax = 3 * domain.paradict['nside'] - 1
+ mmax = lmax
+ return LMSpace(lmax=lmax, mmax=mmax, dtype=np.dtype('complex128'))
+
@staticmethod
def check_codomain(domain, codomain):
if not isinstance(domain, HPSpace):
diff --git a/transformations/lmgltransformation.py b/transformations/lmgltransformation.py
index 7d9e6a19f649afb4adf27d9f43c5f045b0c816b5..0bf90c60bea135c3bcc92943f1ade7d0be556b81 100644
--- a/transformations/lmgltransformation.py
+++ b/transformations/lmgltransformation.py
@@ -9,7 +9,7 @@ gl = gdi.get('libsharp_wrapper_gl')
class LMGLTransformation(Transformation):
- def __init__(self, domain, codomain, module=None):
+ def __init__(self, domain, codomain=None, module=None):
if gdi.get('libsharp_wrapper_gl') is None:
raise ImportError(
"The module libsharp is needed but not available.")
@@ -20,6 +20,46 @@ class LMGLTransformation(Transformation):
else:
raise ValueError("ERROR: Incompatible codomain!")
+ @staticmethod
+ def get_codomain(domain):
+ """
+ Generates a compatible codomain to which transformations are
+ reasonable, i.e.\ a pixelization of the two-sphere.
+
+ Parameters
+ ----------
+ domain : LMSpace
+ Space for which a codomain is to be generated
+
+ Returns
+ -------
+ codomain : HPSpace
+ A compatible codomain.
+
+ References
+ ----------
+ .. [#] M. Reinecke and D. Sverre Seljebotn, 2013,
+ "Libsharp - spherical
+ harmonic transforms revisited";
+ `arXiv:1303.4945 <http://www.arxiv.org/abs/1303.4945>`_
+ """
+ if domain is None:
+ raise ValueError('ERROR: cannot generate codomain for None')
+
+ if not isinstance(domain, LMSpace):
+ raise TypeError('ERROR: domain needs to be a LMSpace')
+
+ if domain.dtype == np.dtype('complex64'):
+ new_dtype = np.float32
+ elif domain.dtype == np.dtype('complex128'):
+ new_dtype = np.float64
+ else:
+ raise ValueError('ERROR: unsupported domain dtype')
+
+ nlat = domain.paradict['lmax'] + 1
+ nlon = domain.paradict['lmax'] * 2 + 1
+ return GLSpace(nlat=nlat, nlon=nlon, dtype=new_dtype)
+
@staticmethod
def check_codomain(domain, codomain):
if not isinstance(domain, LMSpace):
diff --git a/transformations/lmhptransformation.py b/transformations/lmhptransformation.py
index 77643e296f39bf4e7fe4de2256ebf26c567f8673..c9f00bab5b874ce18fdc7be356dc3ccc1f506607 100644
--- a/transformations/lmhptransformation.py
+++ b/transformations/lmhptransformation.py
@@ -9,7 +9,7 @@ hp = gdi.get('healpy')
class LMHPTransformation(Transformation):
- def __init__(self, domain, codomain, module=None):
+ def __init__(self, domain, codomain=None, module=None):
if gdi.get('healpy') is None:
raise ImportError(
"The module libsharp is needed but not available.")
@@ -20,6 +20,37 @@ class LMHPTransformation(Transformation):
else:
raise ValueError("ERROR: Incompatible codomain!")
+ @staticmethod
+ def get_codomain(domain):
+ """
+ Generates a compatible codomain to which transformations are
+ reasonable, i.e.\ a pixelization of the two-sphere.
+
+ Parameters
+ ----------
+ domain : LMSpace
+ Space for which a codomain is to be generated
+
+ Returns
+ -------
+ codomain : HPSpace
+ A compatible codomain.
+
+ References
+ ----------
+ .. [#] K.M. Gorski et al., 2005, "HEALPix: A Framework for
+ High-Resolution Discretization and Fast Analysis of Data
+ Distributed on the Sphere", *ApJ* 622..759G.
+ """
+ if domain is None:
+ raise ValueError('ERROR: cannot generate codomain for None')
+
+ if not isinstance(domain, LMSpace):
+ raise TypeError('ERROR: domain needs to be a LMSpace')
+
+ nside = (domain.paradict['lmax'] + 1) // 3
+ return HPSpace(nside=nside)
+
@staticmethod
def check_codomain(domain, codomain):
if not isinstance(domain, LMSpace):
diff --git a/transformations/rgrgtransformation.py b/transformations/rgrgtransformation.py
index 237d6799d8180b35a6eeec1c5e893e7c2024a8a7..89df9990c59a9ac9887756626953886acd0c86c9 100644
--- a/transformations/rgrgtransformation.py
+++ b/transformations/rgrgtransformation.py
@@ -6,7 +6,7 @@ from nifty import RGSpace, nifty_configuration
class RGRGTransformation(Transformation):
- def __init__(self, domain, codomain, module=None):
+ def __init__(self, domain, codomain=None, module=None):
if self.check_codomain(domain, codomain):
if module is None:
if nifty_configuration['fft_module'] == 'pyfftw':
@@ -25,13 +25,65 @@ class RGRGTransformation(Transformation):
self._transform = FFTW(domain, codomain)
elif module == 'gfft':
self._transform = \
- GFFT(domain, codomain, gdi.get('gfft'))
+ GFFT(domain, codomain, gdi.get('gfft'))
elif module == 'gfft_dummy':
self._transform = \
GFFT(domain, codomain, gdi.get('gfft_dummy'))
else:
raise ValueError("ERROR: incompatible codomain!")
+ @staticmethod
+ def get_codomain(domain, cozerocenter=None, **kwargs):
+ """
+ Generates a compatible codomain to which transformations are
+ reasonable, i.e.\ either a shifted grid or a Fourier conjugate
+ grid.
+
+ Parameters
+ ----------
+ domain: RGSpace
+ Space for which a codomain is to be generated
+ cozerocenter : {bool, numpy.ndarray}, *optional*
+ Whether or not the grid is zerocentered for each axis or not
+ (default: None).
+
+ Returns
+ -------
+ codomain : nifty.rg_space
+ A compatible codomain.
+ """
+ if domain is None:
+ raise ValueError('ERROR: cannot generate codomain for None')
+
+ if not isinstance(domain, RGSpace):
+ raise TypeError('ERROR: domain needs to be a RGSpace')
+
+ # parse the cozerocenter input
+ if cozerocenter is None:
+ cozerocenter = domain.paradict['zerocenter']
+ # if the input is something scalar, cast it to a boolean
+ elif np.isscalar(cozerocenter):
+ cozerocenter = bool(cozerocenter)
+ else:
+ # cast it to a numpy array
+ if np.size(cozerocenter) == 1:
+ cozerocenter = np.asscalar(cozerocenter)
+ elif np.size(cozerocenter) != len(domain.shape):
+ raise ValueError('ERROR: size mismatch (' +
+ str(np.size(cozerocenter)) + ' <> ' +
+ str(domain.shape) + ')')
+
+ # calculate the initialization parameters
+ distances = 1 / (np.array(domain.paradict['shape']) *
+ np.array(domain.distances))
+ complexity = {0: 1, 1: 0, 2: 2}[domain.paradict['complexity']]
+
+ new_space = RGSpace(domain.paradict['shape'], zerocenter=cozerocenter,
+ complexity=complexity, distances=distances,
+ harmonic=bool(not domain.harmonic))
+
+ return new_space
+
@staticmethod
def check_codomain(domain, codomain):
if not isinstance(domain, RGSpace):
diff --git a/transformations/transformation.py b/transformations/transformation.py
index 3232248f60e831a911a129114da5928ffa4eaadb..228715be5572ed94694ba40b6ca77b58961c80dd 100644
--- a/transformations/transformation.py
+++ b/transformations/transformation.py
@@ -4,7 +4,7 @@ class Transformation(object):
method for all transforms.
"""
- def __init__(self, domain, codomain, module=None):
+ def __init__(self, domain, codomain=None, module=None):
pass
def transform(self, val, axes=None, **kwargs):