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cythonmagic.py
200 lines | 7.0 KiB | text/x-python | PythonLexer
# -*- coding: utf-8 -*-
"""
Cython related magics.
Author:
* Brian Granger
Parts of this code were taken from Cython.inline.
"""
#-----------------------------------------------------------------------------
# Copyright (C) 2010-2011, IPython Development Team.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file COPYING.txt, distributed with this software.
#-----------------------------------------------------------------------------
import io
import os, sys
import imp
try:
import hashlib
except ImportError:
import md5 as hashlib
from distutils.core import Distribution, Extension
from distutils.command.build_ext import build_ext
from IPython.core.magic import Magics, magics_class, cell_magic
from IPython.testing.skipdoctest import skip_doctest
from IPython.core.magic_arguments import (
argument, magic_arguments, parse_argstring
)
from IPython.utils import py3compat
import Cython
from Cython.Compiler.Errors import CompileError
from Cython.Compiler.Main import Context, default_options
from Cython.Build.Dependencies import cythonize
@magics_class
class CythonMagics(Magics):
def __init__(self, shell):
super(CythonMagics,self).__init__(shell)
self._reloads = {}
self._code_cache = {}
def _import_all(self, module):
for k,v in module.__dict__.items():
if not k.startswith('__'):
self.shell.push({k:v})
@cell_magic
def cython_inline(self, line, cell):
"""Compile and run a Cython code cell using Cython.inline.
This magic simply passes the body of the cell to Cython.inline
and returns the result. If the variables `a` and `b` are defined
in the user's namespace, here is a simple example that returns
their sum::
%%cython_inline
return a+b
For most purposes, we recommend the usage of the `%%cython` magic.
"""
locs = self.shell.user_global_ns
globs = self.shell.user_ns
return Cython.inline(cell, locals=locs, globals=globs)
@cell_magic
def cython_pyximport(self, line, cell):
"""Compile and import a Cython code cell using pyximport.
The contents of the cell are written to a `.pyx` file in the current
working directory, which is then imported using `pyximport`. This
magic requires a module name to be passed::
%%cython_pyximport modulename
def f(x):
return 2.0*x
The compiled module is then imported and all of its symbols are injected into
the user's namespace. For most purposes, we recommend the usage of the
`%%cython` magic.
"""
module_name = line.strip()
if not module_name:
raise ValueError('module name must be given')
fname = module_name + '.pyx'
with io.open(fname, 'w', encoding='utf-8') as f:
f.write(cell)
if 'pyximport' not in sys.modules:
import pyximport
pyximport.install(reload_support=True)
if module_name in self._reloads:
module = self._reloads[module_name]
reload(module)
else:
__import__(module_name)
module = sys.modules[module_name]
self._reloads[module_name] = module
self._import_all(module)
@magic_arguments()
@argument(
'-c', '--compile-args', action='append', default=[],
help="Extra flags to pass to compiler via the `extra_compile_args` Extension flag (can be specified multiple times)."
)
@argument(
'-l', '--lib', action='append', default=[],
help="Add a library to link the extension against (can be specified multiple times)."
)
@argument(
'-I', '--include', action='append', default=[],
help="Add a path to the list of include directories (can be specified multiple times)."
)
@argument(
'-f', '--force', action='store_true', default=False,
help="Force the compilation of the pyx module even if it hasn't changed"
)
@cell_magic
def cython(self, line, cell):
"""Compile and import everything from a Cython code cell.
The contents of the cell are written to a `.pyx` file in the
directory `IPYTHONDIR/cython` using a filename with the hash of the code.
This file is then cythonized and compiled. The resulting module
is imported and all of its symbols are injected into the user's
namespace. The usage is similar to that of `%%cython_pyximport` but
you don't have to pass a module name::
%%cython
def f(x):
return 2.0*x
"""
args = parse_argstring(self.cython, line)
code = cell if cell.endswith('\n') else cell+'\n'
lib_dir = os.path.join(self.shell.ipython_dir, 'cython')
cython_include_dirs = ['.']
force = args.force
quiet = True
ctx = Context(cython_include_dirs, default_options)
key = code, sys.version_info, sys.executable, Cython.__version__
module_name = "_cython_magic_" + hashlib.md5(str(key).encode('utf-8')).hexdigest()
so_ext = [ ext for ext,_,mod_type in imp.get_suffixes() if mod_type == imp.C_EXTENSION ][0]
module_path = os.path.join(lib_dir, module_name+so_ext)
if not os.path.exists(lib_dir):
os.makedirs(lib_dir)
if force or not os.path.isfile(module_path):
c_include_dirs = args.include
if 'numpy' in code:
import numpy
c_include_dirs.append(numpy.get_include())
pyx_file = os.path.join(lib_dir, module_name + '.pyx')
pyx_file = py3compat.cast_bytes_py2(pyx_file, encoding=sys.getfilesystemencoding())
with io.open(pyx_file, 'w', encoding='utf-8') as f:
f.write(code)
extension = Extension(
name = module_name,
sources = [pyx_file],
include_dirs = c_include_dirs,
extra_compile_args = args.compile_args,
libraries = args.lib,
)
dist = Distribution()
config_files = dist.find_config_files()
try:
config_files.remove('setup.cfg')
except ValueError:
pass
dist.parse_config_files(config_files)
build_extension = build_ext(dist)
build_extension.finalize_options()
try:
build_extension.extensions = cythonize([extension], ctx=ctx, quiet=quiet)
except CompileError:
return
build_extension.build_temp = os.path.dirname(pyx_file)
build_extension.build_lib = lib_dir
build_extension.run()
self._code_cache[key] = module_name
module = imp.load_dynamic(module_name, module_path)
self._import_all(module)
_loaded = False
def load_ipython_extension(ip):
"""Load the extension in IPython."""
global _loaded
if not _loaded:
ip.register_magics(CythonMagics)
_loaded = True