.help cvepower Jun95 "Curfit Package" .ih NAME cvepower -- compute the errors of the equivalent power series .ih SYNOPSIS cvepower (cv, y, weight, yfit, npts, chisqr, errors) .nf pointer cv # curve descriptor real y[] # array of y data points weight weight[] # array of weights real yfit[] # array of fitted data points int npts # number of points real chisqr # the standard deviation of the fit real errors[] # standard deviations of the power series coefficients .fi .ih ARGUMENTS .ls cv Pointer to the curve descriptor structure .le .ls y Array of y data points .le .ls yfit Array of fitted y values .le .ls npts The number of points .le .ls chisqr Reduced chi-squared of the fit. .le .ls errors Array of standard deviations of the equivalent power series coefficients. .le .ih DESCRIPTION Calculate the reduced chi-squared of the fit and the standard deviation of the equivalent power series coefficients for fitted Legendre and Chebyshev polynomials. The errors are rescaled to the equivalent power series and to the original data range. .ih NOTES The standard deviation of the fit is the square root of the sum of the weighted squares of the residuals divided by the number of degrees of freedom. If the weights are equal, then the reduced chi-squared is the variance of the fit The error of the j-th coefficient is the square root of the j-th diagonal element of the inverse of the data matrix. If the weights are equal to one, then the errors are scaled by the square root of the variance of the data. .ih SEE ALSO .endhelp