commit 0a891d70ded5fa8b1e6491529a3b531f521b5ae1
author Guido van Rossum <guido@dropbox.com> Mon Aug 15 09:12:52 2016 -0700
committer Guido van Rossum <guido@dropbox.com> Mon Aug 15 09:12:52 2016 -0700
tree e26a1c826888bbd3c40b7775406062ab1b32cca5
parent 6349612a8e5d5fcb3405e59242b6a2df3127585a

Issue #12345: Add mathemathcal constant tau to math and cmath.

Patch by Lisa Roach. See also PEP 628.

Modules/cmathmodule.c

diff --git a/Modules/cmathmodule.c b/Modules/cmathmodule.c
index cba42a7..0e7d4db 100644
--- a/Modules/cmathmodule.c
+++ b/Modules/cmathmodule.c
@@ -1239,6 +1239,7 @@
     PyModule_AddObject(m, "pi",
                        PyFloat_FromDouble(Py_MATH_PI));
     PyModule_AddObject(m, "e", PyFloat_FromDouble(Py_MATH_E));
+    PyModule_AddObject(m, "tau", PyFloat_FromDouble(Py_MATH_TAU)); /* 2pi */
 
     /* initialize special value tables */