Gavin Kistner
1/9/2007 8:38:00 PM
From: Ilmari Heikkinen [mailto:ilmari.heikkinen@gmail.com]
> On 1/9/07, Phrogz <gavin@refinery.com> wrote:
> > In addition to the answers by others, what would you do for those
math
> > functions whose arity isn't 1?
> >
> > Math.methods(false).select{ |n| Math.method(n).arity != 1 }
> > #=> ["hypot", "atan2", "ldexp"]
> >
> > All three take two arguments. While 3.hypot(4) *might* make
> > sense--given one leg of a right triangle, how long is the hypotenuse
to
> > a given other leg--30.atan2( 40 ) makes little sense to me.
>
> hypot and atan are vector methods, so [30, 40].atan2, [3,4].hypot
> would be correct in the OO-sense, much like #max and #min are in Array
> and not Math (compare to e.g. JavaScript where there is Math.max and
> Math.min)
Good argument. In fact, one of them is there already:
require 'matrix'
Vector[3,4].r #=> 5.0