Math: n-th root, logarithm with arbitrary base

Erik Corry erik.corry at gmail.com
Mon Dec 19 23:55:54 PST 2011


2011/12/19 Axel Rauschmayer <axel at rauschma.de>:
> But wouldn’t that rather be a reason for making these functions part of the
> core language?

MS have proposed log2, log10, log1p.  This makes more sense to me.
These already exist and are useful in other languages and are not too
hard to implement.

If we go beyond that it would be nice to see a sample implementation
that is not either trivial or inaccurate or both?

> On Dec 19, 2011, at 8:48 , Erik Corry wrote:
>
> Both the proposed implementations do fp rounding twice, and so produce
> an inaccurate answer.  I think we should probably leave it to the user
> to define incorrect math functions, rather than bake them into the
> language.
>
> I haven’t seen these two functions among the proposed additions for Math
> (should these be in a math module?):
>
>
>    function nthRoot(n, x) {
>
>        return Math.pow(x, 1/n);
>
>    }
>
>
>    function log_b(b, x) {
>
>        return Math.log(x) / Math.log(b);
>
>    }
>
>
> Have they been considered and rejected?
>
>
> --
> Dr. Axel Rauschmayer
> axel at rauschma.de
>
> home: rauschma.de
> twitter: twitter.com/rauschma
> blog: 2ality.com
>
>
>


More information about the es-discuss mailing list