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Re: Curve fitting errors
Posted:
Dec 12, 2012 9:46 AM


"Sarah " <skragt@gmail.com> wrote in message news:ka87j8$gll$1@newscl01ah.mathworks.com... > I am attempting to fit a large set of data and locate peaks using a > Gaussian function. I am not familiar with Matlab, and have started writing > code for it, but I get an error message. "Undefined function 'minus' for > input arguments of type 'dataset'" > > > load('hcldcl25th1.mat') > x=hcldcl25th1(:,1); > y=hcldcl25th1(:,2); > f(1)=2; > f(2)=4; > f(3)=2798; > fittype=(f(1)*exp(((xf(3)).^2.*(4*log(2)))./(f(2).^2))); > > f(1), f(2), and f(3) are my initial guesses. What do I need to do, or what > am I doing wrong?
From the error, the data in your MATfile is stored in a dataset object. The arithmetic operations (like PLUS, MINUS, etc.) aren't defined for dataset objects. You will need to extract the data from the dataset object before you can perform arithmetic on the data. [After all, it wouldn't make sense to add the patient's name and the patient's age, would it?]
http://www.mathworks.com/help/stats/datasetarraycolumns.html
http://www.mathworks.com/help/stats/performdatasetcalculations.html
 Steve Lord slord@mathworks.com To contact Technical Support use the Contact Us link on http://www.mathworks.com



