On Fri, 2010-10-22 at 17:29 -0700, James Redford wrote:
> If maxima-init.mac has fpprec:32; or higher precision, then the below happens:
>
> (%i1) load(mnewton);
> (%o1) C:/program1/maxima/share/maxima/5.22.1/share/contrib/mnewton.mac
> (%i2) mnewton(cos(x)=1/2,x,0.99);
> mnewton: the process doesn't converge or it converges too slowly.
> (%o2) []
> (%i3)
>
>
> If one then changes fpprec: in the interactive session, it has no effect: mnewton still won't work with cos(x). Yet in the interactive session, if maxima-init.mac has fpprec:31; or lower precision, one can set fpprec: much higher and mnewton will work.
>
> This bug with mnewton does not occur with sin(x), tan(x) or atan(x), which are some examples I tried.
>
> Below is the Maxima version I'm using:
>
> Maxima version: 5.22.1
> Maxima build date: 11:48 8/13/2010
> Host type: i686-pc-mingw32
> Lisp implementation type: GNU Common Lisp (GCL)
> Lisp implementation version: GCL 2.6.8
>
I observe the same bug with Maxima 5.22post/ SBCL 1.0.29.11
Thank you very much for discovering and reporting that bug. We will
investigate it and try to solve it.
Regards,
Jaime