Feature #4897

Define Math::TAU and BigMath.TAU. The "true" circle constant, Tau=2*Pi. See

Added by sbaird (Simon Baird) over 9 years ago. Updated about 4 years ago.

Target version:


Firstly please read the Tau Manifesto at . It's quite long but essential to understanding why this is a good idea.

Here is a patch on trunk that implements this:

Allow me to anticipate and respond in advance to some common objections:

  1. It's easy to define it yourself so why put this in core.
    Possibly correct, but I think this is the right thing to do. Tau is important. And it's a pretty small patch.

  2. If this constant goes in then pretty soon someone will want every other math constant and there are hundreds of them. (Slippery slope argument).
    The circle constant is one of the two most important numbers is mathematics. It's not just another math constant. We already define Pi.


tau.patch (1.2 KB) tau.patch phluid61 (Matthew Kerwin), 02/27/2013 02:25 PM
tau.patch (1.2 KB) tau.patch phluid61 (Matthew Kerwin), 02/28/2013 07:10 AM

Related issues

Related to Ruby master - Feature #13694: Add Tau constant to MathRejectedActions
Has duplicate Ruby master - Feature #17496: Add constant Math::TAUOpenActions

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