Issue #10225 has been updated by David MacMahon.


 FWIW, the Ruby/GSL gem already provides support for this (and many other things):
 
 ```
 $ ruby -r gsl -e 'p GSL::Cdf::gaussian_P(1)'
 0.8413447460685429
 ```
 
 On Sep 10, 2014, at 11:26 PM, mail / tanakakazuki.com wrote:
 
 > Issue #10225 has been reported by gogo tanaka.
 > 
 > ----------------------------------------
 > Feature #10225: [PATCH] *math.c: New method Math.normcdf 
 > https://bugs.ruby-lang.org/issues/10225
 > 
 > * Author: gogo tanaka
 > * Status: Open
 > * Priority: Normal
 > * Assignee: 
 > * Category: 
 > * Target version: 
 > ----------------------------------------
 > I know it looks kind of arbitrary or unnecessary feature ,but I believe that
 > 
 > to provide such a feature as official is helpful to make people we couldn't reach so far have interest in Ruby.
 > 
 > (Actually only this feature is not enough to do that..)
 > 
 > By the way I still wonder whether naming method make sense.
 > 
 > Debating between ...
 > 
 > ```
 > Math::pnorm   -> R language use this
 > Math::phi     -> Euler's totient function is more popular as phi,
 > Math::ncdf
 > Math::guesscdf
 > Math::cdf_of_norm,
 > Math::cdf_of_guess
 > ```
 > 
 > Finally I come to the conclusion Math::normcdf is most proper length, meaning and has no other worries.
 > 
 > ---Files--------------------------------
 > _ math.c New method Math.normcdf.PATCH (1.04 KB)
 > _ test_math.rb Add tests for Math.normcdf.PATCH (609 Bytes)
 > _ NEWS About Math.normcdf.PATCH (488 Bytes)
 > 
 > 
 > -- 
 > https://bugs.ruby-lang.org/

----------------------------------------
Feature #10225: [PATCH] *math.c: New method Math.normcdf 
https://bugs.ruby-lang.org/issues/10225#change-48855

* Author: gogo tanaka
* Status: Open
* Priority: Normal
* Assignee: 
* Category: math
* Target version: current: 2.2.0
----------------------------------------
I know it looks kind of arbitrary or unnecessary feature ,but I believe that

to provide such a feature as official is helpful to make people we couldn't reach so far have interest in Ruby.

(Actually only this feature is not enough to do that..)

By the way I still wonder whether naming method make sense.

Debating between ...

```
Math::pnorm   -> R language use this
Math::phi     -> Euler's totient function is more popular as phi,
Math::ncdf
Math::guesscdf
Math::cdf_of_norm,
Math::cdf_of_guess
```

Finally I come to the conclusion Math::normcdf is most proper length, meaning and has no other worries.

---Files--------------------------------
_ math.c New method Math.normcdf.PATCH (1.04 KB)
_ test_math.rb Add tests for Math.normcdf.PATCH (609 Bytes)
_ NEWS About Math.normcdf.PATCH (488 Bytes)


-- 
https://bugs.ruby-lang.org/