Hi, I have data given in cartesian coordinates and want to fit it with a function I defined via "Analysis--->Non-linear curve fit--->Advanced fitting tool". But I would like Origin to interpret the independent variable in the formula as angle and the dependent variable as radial distance, i.e. to explain it that my fitting formula is in polar coordinates, not cartesian. How can I do this? Thanks a lot! M.
Oh my...how come? :-) And what if I do it this way: I want to fit data with function which is in polar coordinates given as follows: r=a+b*theta. But I write the formula like SQRT(xx+yy)=a+b*atan(y/x)...now it is in cartesian coordinates, but Fitting Wizard still won't perform the fitting, complaining about some mistake in User defined function formula. Can someone please explain me why?
Fitting with function given in polar coordinates
Posted - 06/08/2010 : 11:47:03 AM
