Re: [Help-gsl] Finding roots of polynomial - how?

[Brian Gough]

Anders Misfeldt writes:
 > Hi,
 > 
 > I'm trying to find out how to find the roots of a 2nd degree polynomial 
 > using the Brent routine in GSL. When I run my program I get:
 > 
 > gsl: brent.c:74: ERROR: endpoints do not straddle y=0
 > Default GSL error handler invoked.
 > Aborted
 > 
 > What am I doing wrong (the code is written below)? How can I write out 
 > all the different roots?

Hello, 

The section on "Root Bracketing Algorithms" in the "1d Root-Finding"
Chapter of the GSL Reference Manual describes the constraints on the
initial interval [a,b].

-- 
regards

Brian Gough

Network Theory Ltd,
Publishing Free Software Manuals --- http://www.network-theory.co.uk/