problems with precision
- To: mathgroup at smc.vnet.net
- Subject: [mg7646] problems with precision
- From: Axel Breuer <u970870 at student.dtu.dk>
- Date: Tue, 24 Jun 1997 03:36:09 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Hello,
I am a french student doing a trainee on mathematica. There is another
team having the same project as I have but it's working with Maple.
We had to calculate with high accuracy (more than 20 digits) the solution
of a 2 dimensional non-linear system. The problem to solve was very easy.
But Maple and Mathematica agreed only on the 15 first digits. I used the
function SetPrecision. Is there another function to set calculus precision
?
Here is the listing of my routine in Mathematica :
rr=Table[FindRoot[{x+Cos[y]*Sinh[x]==0,y+Sin[y]*Cosh[x]==0},{x,N[Abs[Cos[(2*p-1)*Pi+Pi/4]]Sqrt[((2*p-1)*Pi+Pi/4/Sin[(2*p-1)*Pi+Pi/4]^2)-1]]},{y,(2*p-1)*Pi+Pi/4}]
, {p, 1, 20, 1}]
rr=SetPrecision[rr,20]
ListPlot[{x, y} /. rr]
r={x, y} /. rr;