Subject: [PATCH] limits of fresnel_c and fresnel_s
From: John Lapeyre
Date: Sat, 07 Sep 2013 00:32:53 +0200
On 09/07/2013 12:00 AM, Stavros Macrakis wrote:
> integrate(cos(x^2),x) gives a result in terms of erf which seems
perfectly reasonable. Maxima doesn't guarantee any particular form of an
integral.
Yeah, it's not unreasonable.
More important are the missing limits.
>
> -s
>
>
> On Fri, Sep 6, 2013 at 4:14 PM, John Lapeyre
<lapeyre.math122a at gmail.com> wrote:
>
> Hello,
>
> I am attaching a patch for the limits of fresnel_c
> and fresnel_s.
>
> Also, we have
> (%i14) diff(fresnel_c(x),x);
> (%o14) cos(%pi*x^2/2)
> (%i15) diff(fresnel_s(x),x);
> (%o15) sin(%pi*x^2/2)
>
> But integrating cos(x^2) and sin(x^2) give complicated expressions,
> when they should probably return the fresnel integrals... unless there
> is a switch I don't know about.
>
> Tracing gives this:
>
> 1: (DIFFDIV ((%COS SIMP) ((MEXPT SIMP) $X 2)) $X)
> 1: DIFFDIV returned NIL
>
>
> -- John
>
>
> _______________________________________________
> Maxima mailing list
> Maxima at math.utexas.edu
> http://www.math.utexas.edu/mailman/listinfo/maxima
>
>