lsqcurvefit() moved from Matlab to toolbox?

Hi all - do I misremember that lsqcurvefit() used to be a core matlab function? I've not used it in a few releases and was just surprised to find I need a toolbox for basic nonlinear fitting. Just testing my memory here.

[Rik]

I haven't checked, but not to my recollection. I believe you always needed fminsearch for things \ can't handle. But after I check I may turn out to be wrong. Do you have a range of releases you expect this change (if it is a change) to have occurred?

Answer 1

[Star Strider]

The lsqucurvefit function has always been in the Optimization Toolbox for as long as I’ve been using MATLAB. You may be referring to fminsearch that is both a basic MATLAB function and in the Optimization Toolbox. You can certainly do nonlinear fitting with it.

Answer 2

[John D'Errico]

You definitely mis-remember this. lsqcurvefit has always been in the optimization toolbox. At least as long as I can recall on this, and my MATLAB memory goes back a long way.

Perhaps in an older release you had, perhaps from an employer, in a galaxy far far away, you may have had that toolbox so you just assumed it was part of MATLAB. But lsqcurvefit has always been where it it now, in the optimization toolbox.

Or, perhaps you are thinking of lsqnonneg. I'm pretty sure that lives in MATLAB proper, not provided with the optimization toolbox. (Although lsqnonneg is listed as part of the optimization toolbox.)