#179 ratsimp bug

closed
nobody
5
2007-08-19
2002-11-08
No

In Maxima 5.5/Windows/gcl

expr:

-4*(SQRT(5)-1)/(SQRT(5)*(10-2*SQRT(5))*
((4*x+SQRT(5)+1)^2/(10-2*SQRT(5))+1))
-4*(SQRT(5)+1)/(SQRT(5)*(2*SQRT(5)+10)*
((4*x-SQRT(5)+1)^2/(2*SQRT(5)+10)+1))-
(SQRT(5)+3)*(4*x+SQRT(5)+1)/
((10*SQRT(5)+10)*(2*x^2+(SQRT(5)+1)*x+2))
+(SQRT(5)-3)*(4*x-SQRT(5)+1)/
((10-10*SQRT(5))*(2*x^2+(1-SQRT(5))*x+2))
+1/(5*(x-1))

expr,x=1.1,numer => 1.638...

exprsimp: ratsimp(expr)

exprsimp,x=1.1,numer => 0.384...n (!!!)

Other simplifications do not run into this problem, e.g.
ratsimp(factor(expr)), ratsimp(rat(expr)), which nicely
yield 1/(x^5-1).

Discussion

  • Robert Dodier

    Robert Dodier - 2006-07-01

    Logged In: YES
    user_id=501686

    Still present in 5.9.3cvs / sbcl 0.9.9.

     
  • Robert Dodier

    Robert Dodier - 2006-07-01
    • labels: --> 460522
     
  • Robert Dodier

    Robert Dodier - 2006-08-27
    • labels: 460522 --> Lisp Core - Simplification
     
  • Dan Gildea

    Dan Gildea - 2007-08-04

    Logged In: YES
    user_id=1797506
    Originator: NO

    Seems OK in 5.12.0.

     
  • Dan Gildea

    Dan Gildea - 2007-08-04
    • status: open --> pending
     
  • SourceForge Robot

    • status: pending --> closed
     
  • SourceForge Robot

    Logged In: YES
    user_id=1312539
    Originator: NO

    This Tracker item was closed automatically by the system. It was
    previously set to a Pending status, and the original submitter
    did not respond within 14 days (the time period specified by
    the administrator of this Tracker).

     

Log in to post a comment.

Get latest updates about Open Source Projects, Conferences and News.

Sign up for the SourceForge newsletter:

JavaScript is required for this form.





No, thanks