System configuration — NumPy v1.11 Manual (original) (raw)

When NumPy is built, information about system configuration is recorded, and is made available for extension modules using Numpy’s C API. These are mostly defined in numpyconfig.h (included inndarrayobject.h). The public symbols are prefixed by NPY_*. Numpy also offers some functions for querying information about the platform in use.

For private use, Numpy also constructs a config.h in the NumPy include directory, which is not exported by Numpy (that is a python extension which use the numpy C API will not see those symbols), to avoid namespace pollution.

Data type sizes¶

The NPY_SIZEOF_{CTYPE} constants are defined so that sizeof information is available to the pre-processor.

NPY_SIZEOF_SHORT¶

NPY_SIZEOF_INT¶

NPY_SIZEOF_LONG¶

NPY_SIZEOF_LONGLONG¶

sizeof(longlong) where longlong is defined appropriately on the platform.

NPY_SIZEOF_PY_LONG_LONG¶

NPY_SIZEOF_FLOAT¶

NPY_SIZEOF_DOUBLE¶

NPY_SIZEOF_LONG_DOUBLE¶

NPY_SIZEOF_PY_INTPTR_T¶

Size of a pointer on this platform (sizeof(void *)) (A macro defines NPY_SIZEOF_INTP as well.)

Platform information¶

NPY_CPU_X86¶

NPY_CPU_AMD64¶

NPY_CPU_IA64¶

NPY_CPU_PPC¶

NPY_CPU_PPC64¶

NPY_CPU_SPARC¶

NPY_CPU_SPARC64¶

NPY_CPU_S390¶

NPY_CPU_PARISC¶

New in version 1.3.0.

CPU architecture of the platform; only one of the above is defined.

Defined in numpy/npy_cpu.h

NPY_LITTLE_ENDIAN¶

NPY_BIG_ENDIAN¶

NPY_BYTE_ORDER¶

New in version 1.3.0.

Portable alternatives to the endian.h macros of GNU Libc. If big endian, NPY_BYTE_ORDER == NPY_BIG_ENDIAN, and similarly for little endian architectures.

Defined in numpy/npy_endian.h.

PyArray_GetEndianness()¶

New in version 1.3.0.

Returns the endianness of the current platform. One of NPY_CPU_BIG, NPY_CPU_LITTLE, or NPY_CPU_UNKNOWN_ENDIAN.