Re: Mathematica 7 compares to other languages
On Dec 11, 4:53 pm, "William James" <[EMAIL PROTECTED]> wrote:
> William James wrote:
> > John W Kennedy wrote:
>
> > > Xah Lee wrote:
> > > > In lisp, python, perl, etc, you'll have 10 or so lines. In C or
> > > > Java, you'll have 50 or hundreds lines.
>
> > > Java:
>
> > > static float[] normal(final float[] x) {
> > > float sum = 0.0f;
> > > for (int i = 0; i < x.length; ++i) sum += x[i] * x[i];
> > > final float divisor = (float) Math.sqrt(sum);
> > > float[] a = new float[x.length];
> > > for (int i = 0; i < x.length; ++i) a[i] = x[i]/divisor;
> > > return a;
> > > }
>
> > "We don't need no stinkin' loops!"
>
> > SpiderMonkey Javascript:
>
> > function normal( ary )
> > { div=Math.sqrt(ary.map(function(x) x*x).reduce(function(a,b) a+b))
> > return ary.map(function(x) x/div)
> > }
>
> The variable "div" shouldn't be global.
>
> function normal( ary )
> { var div = Math.sqrt(
> ary.map(function(x) x*x).reduce(function(a,b) a+b) )
> return ary.map(function(x) x/div)
>
> }
>
>
Chicken Scheme:
(require 'srfi-1)
(define (norm vec)
(map (cute / <> (sqrt (reduce + 0 (map (cute expt <> 2) vec
vec))
Cute huh? ;-)
--
http://mail.python.org/mailman/listinfo/python-list
Re: Mathematica 7 compares to other languages
On Dec 11, 7:50 pm, [EMAIL PROTECTED] wrote:
> On Dec 11, 4:53 pm, "William James" <[EMAIL PROTECTED]> wrote:
>
>
>
> > William James wrote:
> > > John W Kennedy wrote:
>
> > > > Xah Lee wrote:
> > > > > In lisp, python, perl, etc, you'll have 10 or so lines. In C or
> > > > > Java, you'll have 50 or hundreds lines.
>
> > > > Java:
>
> > > > static float[] normal(final float[] x) {
> > > > float sum = 0.0f;
> > > > for (int i = 0; i < x.length; ++i) sum += x[i] * x[i];
> > > > final float divisor = (float) Math.sqrt(sum);
> > > > float[] a = new float[x.length];
> > > > for (int i = 0; i < x.length; ++i) a[i] = x[i]/divisor;
> > > > return a;
> > > > }
>
> > > "We don't need no stinkin' loops!"
>
> > > SpiderMonkey Javascript:
>
> > > function normal( ary )
> > > { div=Math.sqrt(ary.map(function(x) x*x).reduce(function(a,b) a+b))
> > > return ary.map(function(x) x/div)
> > > }
>
> > The variable "div" shouldn't be global.
>
> > function normal( ary )
> > { var div = Math.sqrt(
> > ary.map(function(x) x*x).reduce(function(a,b) a+b) )
> > return ary.map(function(x) x/div)
>
> > }
>
> Chicken Scheme:
>
> (require 'srfi-1)
> (define (norm vec)
> (map (cute / <> (sqrt (reduce + 0 (map (cute expt <> 2) vec
> vec))
>
> Cute huh? ;-)
Haskell looks the best though:
norm v = map (/ (sqrt (sum (map (^2) v v
--
http://mail.python.org/mailman/listinfo/python-list
Re: Mathematica 7 compares to other languages
On Dec 12, 12:12 am, Xah Lee wrote: > On Dec 11, 6:50 am, the.brown.dragon.b...@gmail.com wrote: > ;; Chicken Scheme. By the.brown.dragon...@gmail.com > (require 'srfi-1) > (define (normalize vec) > (map (cute / <> (sqrt (reduce + 0 (map (cute expt <> 2) vec > vec)) > > Is it possible to make it work in scsh? (i'm running scsh 0.6.4, and > don't know Scheme lisp well) > > Xah > ∑http://xahlee.org/ > > ☄ I don't have scsh but yes - it should work fine. "cute" is an SRFI (http://srfi.schemers.org/srfi-26/) which should be available. cheers, BD -- http://mail.python.org/mailman/listinfo/python-list
