Curve fitting tool unavailable?

Attempting to use the command "fit", even for a very simple data set returns: Undefined function 'fit' for input arguments of type 'double'.

typing cftool returns not available.

Anyone know why or how to fix this? I am running MATLAB off a cluster, not a personal computer if that makes a difference.

Sorry if the question is silly. ;/

[Geoff Hayes]

The function fit is from the Curve Fitting Toolbox ( http://www.mathworks.com/help/curvefit/fit.html). In the Command Window, type ver too list your version of MATLAB and toolbox information to see if you have this toolbox.

[Darya]

Is the curve fitting toolbox part of another toolbox like statistics or optimization?

[Geoff Hayes]

No, it is its own Toolbox. See Star Strider's solution below for alternatives to the fit function.

[Star Strider]

No. The Curve Fitting Toolbox is a separate Toolbox.

The Statistics Toolbox function nlinfit fits vector dependent variables but has all the statistics you’ll likely ever need.

The Optimization Toolbox function lsqcurvefit can fit matrix dependent variables and allows parameter constraints, but doesn’t have access to all the statistics.

Answer 1

[Star Strider]

If you need to fit data and don’t have access to the Curve Fitting Toolbox, see if you have the Statistics Toolbox or the Optimization Toolbox. Those both have good curve fitting functions.

To see if you have these, type:

which nlinfit -all
which lsqcurvefit -all

in the MATLAB Command Window.

If all else fails, you can use fminsearch.