Merge pull request #55 from mreineck/main

Draft/request for discussion: optional ducc0-based backend for SHTs

Author: mdavezac

.github/workflows/python.yml

@@ -31,7 +31,7 @@ jobs:
           python -m pip install scikit-build
 
       - name: Install pyssht
-        run: pip install -e .[dev]
+        run: pip install -e .[dev,ducc0]
 
       - name: run pytest
         run: pytest tests/test_pyssht.py
@@ -85,7 +85,7 @@ jobs:
       - name: Setup environment
         run: |
           python -m pip install --upgrade pip wheel
-          python -m pip install conan pytest
+          python -m pip install conan pytest ducc0
           conan profile new default --detect
 
       - name: Build wheels

.gitignore

@@ -5,8 +5,8 @@ SSHT.sublime-workspace
 build/
 *.DS_Store
 *.idea/
-src/python/*.c
-src/python/*.so
+src/pyssht/*.c
+src/pyssht/*.so
 
 CMakeCache.txt
 CMakeFiles/

setup.py

@@ -18,6 +18,7 @@
     "conan",
     "pip!=20.0.0,!=20.0.1",
     "pytest",
+    "ducc0>=0.16",
 ]
 
 long_description = (
@@ -35,7 +36,7 @@
         "Y. Wiaux",
     ],
     install_requires=["numpy", "scipy"],
-    extras_require={"dev": dev_requirements},
+    extras_require={"dev": dev_requirements, "ducc0": ["ducc0>=0.16"]},
     description="Fast spin spherical transforms",
     long_description=long_description,
     long_description_content_type="text/markdown",

src/pyssht/CMakeLists.txt

@@ -1,10 +1,15 @@
-add_cython_target(cython_sources pyssht.pyx C PY3)
-add_library(pyssht MODULE ${cython_sources})
-python_extension_module(pyssht)
-target_link_libraries(pyssht ssht)
-target_include_directories(pyssht PUBLIC "${PROJECT_SOURCE_DIR}/src/c"
-                                         ${NumPy_INCLUDE_DIRS})
+add_cython_target(cpyssht_sources cpyssht.pyx C PY3)
+add_cython_target(ducc0_sources ducc_interface.pyx C PY3)
+add_library(cpyssht MODULE ${cpyssht_sources})
+add_library(ducc_interface MODULE ${ducc0_sources})
+python_extension_module(cpyssht)
+python_extension_module(ducc_interface)
+target_link_libraries(cpyssht ssht)
+target_include_directories(cpyssht PUBLIC "${PROJECT_SOURCE_DIR}/src/c"
+                                          ${NumPy_INCLUDE_DIRS})
+target_include_directories(ducc_interface PUBLIC ${NumPy_INCLUDE_DIRS})
 if(WIN32)
-    target_compile_definitions(pyssht PUBLIC MS_WIN64)
+    target_compile_definitions(cpyssht PUBLIC MS_WIN64)
+    target_compile_definitions(ducc_interface PUBLIC MS_WIN64)
 endif()
-install(TARGETS pyssht LIBRARY DESTINATION src/pyssht)
+install(TARGETS cpyssht ducc_interface LIBRARY DESTINATION src/pyssht)

src/pyssht/SSHT_Python_Documentation.md

@@ -1,6 +1,11 @@
 # SSHT Python Documentation
 
-This guide is intended to explain the python interface of SSHT. For a description of the workings of SSHT see [here](http://astro-informatics.github.io/ssht/ "SSHT documentation")
+This guide is intended to explain the python interface of SSHT. For a
+description of the workings of SSHT see
+[here](http://astro-informatics.github.io/ssht/ "SSHT documentation"). The
+python package also offers an interface to some of the functionality from
+[ducc0](https://pypi.org/project/ducc0/), including forward and inverse
+transforms.
 
 ## pyssht.forward
 
@@ -22,6 +27,11 @@ Performs the forward spherical harmonic transform.
     4. `'DH'`         [Driscoll & Healy sampling]
     5. `'GL'`         [Gauss-Legendre sampling]
 * `Reality`  determines if the signal is real or complex, Boolean (default = False)
+* `backend` the backend that runs the transforms:
+    1. `'SSHT'` this package
+    2. `'ducc'` interface to [ducc0](https://pypi.org/project/ducc0/). "MW_pole"
+       is not available in this backend.
+* `nthreads`: number of threads when calling into the `'ducc'` backend. Ignored otherwise.
 
 #### Output
 
@@ -54,6 +64,11 @@ Performs the inverse spherical harmonic transform.
     4. `'DH'`         [Driscoll & Healy sampling]
     5. `'GL'`         [Gauss-Legendre sampling]
 * `Reality`  determines if the signal is real or complex, Boolean (default = False)
+* `backend` the backend that runs the transforms:
+    1. `'SSHT'` this package
+    2. `'ducc'` interface to [ducc0](https://pypi.org/project/ducc0/). "MW_pole"
+       is not available in this backend.
+* `nthreads`: number of threads when calling into the `'ducc'` backend. Ignored otherwise.
 
 #### Output
 
@@ -105,6 +120,11 @@ Performs the adjoint of the inverse spherical harmonic transform.
     1. `'MW'`         [McEwen & Wiaux sampling (default)]
     2. `'MWSS'`       [McEwen & Wiaux symmetric sampling]
 * `Reality`  determines if the signal is real or complex, Boolean (default = False)
+* `backend` the backend that runs the transforms:
+    1. `'SSHT'` this package
+    2. `'ducc'` interface to [ducc0](https://pypi.org/project/ducc0/). "MW_pole"
+       is not available in this backend.
+* `nthreads`: number of threads when calling into the `'ducc'` backend. Ignored otherwise.
 
 #### Output
 
@@ -770,10 +790,13 @@ Function to rotate a set of spherical harmonic coefficients by the set of Euler
 * `beta` rotation angle \(\beta\), type `double`
 * `gamma` rotation angle \(\gamma\), type `double`
 * `L` the band limit of the signal, non-zero positive integer
-* `dl_array` if set should be the precomputed small Wigner D matrix for angle \(\beta\) and harmonic band limit `L`. If not set this is calculated in the function.
+* `dl_array` if set should be the precomputed small Wigner D matrix for angle \(\beta\) and harmonic band limit `L`. If not set this is calculated in the function. (This parameter is ignored when using the `ducc` backend.)
 * `M` if set is the azimuthal band limit of the function to be rotated, default `M=L`.
 * `Axisymmetric` set if the function is axisymmetric and axisymmetric harmonic coefficients are parsed.
-* `Keep_dl` if set the output is changed to allow one to keep the computed `dl_array`
+* `Keep_dl` if set the output is changed to allow one to keep the computed `dl_array`. (This parameter is ignored when using the `ducc` backend.)
+* `backend` the backend that runs the transforms:
+    1. `'SSHT'` this package
+    2. `'ducc'` interface to [ducc0](https://pypi.org/project/ducc0/)
 
 #### Output
 

src/pyssht/__init__.py

@@ -4,4 +4,5 @@
 
 __doc__ = (Path(__file__).parent / "SSHT_Python_Documentation.md").read_text()
 
-from .pyssht import *
+from pyssht.exceptions import ssht_spin_error, ssht_input_error  # type: ignore
+from pyssht.cpyssht import *