Sine curve fitting for the given data

I have a set of data,I need to fit the data to sine curve ..

Suggest a code..

Thanks

Answer 1

[LUI PAUL]

try this

cftool(data11(:,1),data11(:,2)); and follow the figure

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Answer 2

[Andreas Goser]

"Suggest a code"...

Well, anyway, let us know if you have the Curve Fitting Tbx or Optimization Tbx available (output of 'ver' command) and provide a sample of data like 20 data points and then we can suggest an approach for you to code.

[Betha Shirisha]

@ Andreas

Yes sir i do have the Curve fitting Tbx. I have attached the file containing the data.

Coloumn 1 represents Time and col 2 is force..

Time interval is 10^(-5) sec

[Torsten]

If xdata is the first column and ydata is the second column of your file data11.txt, you can use

myfun=@(x,xdata)(x(1)*sin(x(2)*xdata+x(3)));
x0=[1; 1; 1];
[x,resnorm] = lsqcurvefit(@myfun,x0,xdata,ydata);

Best wishes

Torsten.

[Torsten]

Sorry, should read

[x,resnorm] = lsqcurvefit(myfun,x0,xdata,ydata);

Best wishes

Torsten.

[Betha Shirisha]

@ Torsten The below messsage is displayed on the command window

lsqcurvefit stopped because the final change in the sum of squares relative to its initial value is less than the default value of the function tolerance