FCHISQ(3M)

NAME
fchisq

DESCRIPTION
function fchisq.f source
  Bevington, page 194. purpose
  evaluate reduced chi square for fit of data
    fchisq = sum ((y-yfit)**2 / sigma**2) / nfree usage
  result = fchisq (y, sigmay, npts, nfree, mode, yfit) description of parameters
  y - array of data points
  sigmay - array of standard deviations for data points
  npts - number of data points
  nfree - number of degrees of freedom
  mode - determines method of weighting least-squares fit
           +1 (instrumental) weight(i) = 1./sigmay(i)**2
            0 (no weighting) weight(i) = 1.
           -1 (statistical) weight(i) = 1./y(i)
  yfit - array of calculated values of y subroutines and function subprograms required
  none