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Introduction. Fitting program - goal is to vary the fit parameters to minimize the chi-square defined as:. function. Fit parameters. data points. errors. f{g,x) = 2πsqrt(length/g). Basketball Movie. Go to the notes for Week 3 find data. Excel file. Y-pos. Y-vel. time. Import to IGOR.
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Introduction Fitting program - goal is to vary the fit parameters to minimize the chi-square defined as: function Fit parameters data points errors f{g,x) = 2πsqrt(length/g)
Basketball Movie Go to the notes for Week 3 find data Excel file Y-pos Y-vel time
Import to IGOR Make waves - called:tt, ypos and yvel Make table - Under Windows - new tableThen cut from the Excel file and pasteinto IGOR table
Fit Data to a Polynomial This dialog box - from choosing Curve Fitting under Analysis in themain menu Specify waves for the fit Built - infunctions areavailable 3 terms or quadratic
Fit in a Range of Data With a graph selected - underthe Graph menu select Show Info - then move cursors overthe data points that define therange to be fitted
Procedure Define error wave and inverse error wave. In this example: err and errinv= 1/err. In the graph of period vs length, use markers for data and show error bars. Define the user-function in the Procedure window. In this example pend Make fitting coefficients wave and set to reasonable starting values. In this example coef.