From help-octave-request at bevo dot che dot wisc dot edu Wed Jul 14 15:15:22 1999 Subject: fsolve features From: "John W. Eaton" To: Rolf Fabian Cc: "'help-octave'" , "'F.Potorti@cnuce.cnr.it'" , "'viveks-octave@me.iitb.ernet.in'" , "'walter@pctc.chemie.uni-erlangen.de'" Date: Wed, 14 Jul 1999 15:13:57 -0500 (CDT) On 5-Jul-1999, Rolf Fabian wrote a number of complaints about Octave's fsolve function including * fsolve is not able to compute complex-valued solutions. * fsolve discards the imaginary part of complex-valued initial guesses. * fsolve discards the imaginary part of complex-valued function evaluations. Note that warnings about discarding the imaginary part of a complex value are given by default, but may be suppressed depending on the setting of the built-in variable ok_to_lose_imaginary_part. The problem is that fsolve is not intended to handle complex-valued functions or find complex-valued solutions. It is based on Minpack's hybrd function, which is only good finding real-valued solutions for real-valued functions. If you have a better solution, please consider providing it as an alternative (submit it to octave-sources, for starters). If it is really better, then perhaps it can become the default method for fsolve. Thanks, jwe --------------------------------------------------------------------- Octave is freely available under the terms of the GNU GPL. To ensure that development continues, see www.che.wisc.edu/octave/giftform.html Instructions for unsubscribing: www.che.wisc.edu/octave/archive.html ---------------------------------------------------------------------