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7. Polynomial Fitting

The POLYFIT program creates a polynomial equation (see Appendix A, Section 1) portrayal of data points (independent variable X, dependent variable Y). Such useful representations of related phenomena have the form:

polynomial equation

where c, a1, a2, a3, ...an are constants, and the "degree" of the polynomial, n, is at least two less than the number of data points. To run the program, insert the disk into the computer drive bay, set the computer for that drive, and enter POLYFIT. Answer the questions regarding the number of data points and desired degree of the fitting. Then enter the pairs of points, X and Y, separated by a comma. The program gives the values of the constant and the polynomial coefficients. Also, an opportunity is provided to use the polynomial to determine any Y value for a given X. An example screen is shown below. The program

Example Screen from POLYFIT

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Download linux version with C source code

Download windows version with C source code

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