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Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>

Author: 3 people

Doc/library/math.rst

@@ -656,8 +656,8 @@ Trigonometric functions
    The vector in the plane from the origin to point ``(x, y)`` makes this angle
    with the positive X axis. The point of :func:`atan2pi` is that the signs of both
    inputs are known to it, so it can compute the correct quadrant for the angle.
-   For example, ``atanpi(1)`` and ``atan2pi(1, 1)`` are both ``.25``, but
-   ``atan2pi(-1, -1)`` is ``-.75``.
+   For example, ``atanpi(1)`` and ``atan2pi(1, 1)`` are both ``0.25``, but
+   ``atan2pi(-1, -1)`` is ``-0.75``.
 
    .. versionadded:: next
 

Doc/whatsnew/3.16.rst

@@ -111,6 +111,7 @@ math
   new functions :func:`math.cospi`, :func:`math.sinpi`, and :func:`math.tanpi`
   take half-turn angle arguments. These functions are recommended by IEEE
   754-2019 and standardized in C23.
+  (Contributed by Jeff Epler in :gh:`150534`.)
 
 os
 --

Modules/mathmodule.c

@@ -312,7 +312,6 @@ m_cospi(double x)
 #define m_cospi cospi
 #endif
 
-
 #ifndef HAVE_SINPI
 /*
    sin(pi*x), giving accurate results for all finite x (especially x