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+Numpy core libraries
+====================
+
+.. sectionauthor:: David Cournapeau
+
+Starting from numpy 1.3.0, we are working on separating the pure C,
+"computational" code from the python dependent code. The goal is twofolds:
+making the code cleaner, and enabling code reuse by other extensions outside
+numpy (scipy, etc...).
+
+Numpy core math library
+-----------------------
+
+The numpy core math library ('npymath') is a first step in this direction. This
+library contains most math-related C99 functionalities, which can be used on
+platforms where C99 is not well supported. Generally, the core math functions
+have the same API as the C99 ones, except for the npy_* prefix.
+
+The available functions are defined in npy_math.h - please refer to this header
+in doubt.
+
+Floating point classification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. cvar:: NPY_NAN
+
+    This macro is defined to a NaN (Not a Number), and is guaranteed to have
+    the signbit unset ('positive' NaN). The corresponding single and extension
+    precision macro are available with the suffix F and L.
+
+.. cvar:: NPY_INFINITY
+
+    This macro is defined to a positive inf. The corresponding single and
+    extension precision macro are available with the suffix F and L.
+
+.. cvar:: NPY_PZERO
+
+    This macro is defined to positive zero. The corresponding single and
+    extension precision macro are available with the suffix F and L.
+
+.. cvar:: NPY_NZERO
+
+    This macro is defined to negative zero (that is with the sign bit set). The
+    corresponding single and extension precision macro are available with the
+    suffix F and L.
+
+.. cfunction:: int npy_isnan(x)
+
+    This is a macro, and is equivalent to C99 isnan: works for single, double
+    and extended precision, and return a non 0 value is x is a NaN.
+
+.. cfunction:: int npy_isfinite(x)
+
+    This is a macro, and is equivalent to C99 isfinite: works for single,
+    double and extended precision, and return a non 0 value is x is neither a
+    NaN or a infinity.
+
+.. cfunction:: int npy_isinf(x)
+
+    This is a macro, and is equivalent to C99 isinf: works for single, double
+    and extended precision, and return a non 0 value is x is infinite (positive
+    and negative).
+
+.. cfunction:: int npy_signbit(x)
+
+    This is a macro, and is equivalent to C99 signbit: works for single, double
+    and extended precision, and return a non 0 value is x has the signbit set
+    (that is the number is negative).
+