NAME
linfit
DESCRIPTION
subroutine linfit.f
source
Bevington, pages 104-105.
purpose
make least-squares fit to a data set with a straight line
usage
call linfit (x, y, sigmay, npts, mode, a, sigmaa,
b, sigmab, r)
description of parameters
x - array of data points for independent variable
y - array of data points for dependent variable
sigmay - array of standard deviations for y data points
npts - number of pairs of data points
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)
a - y intercept of fitted straight line
sigmaa - standard deviation of a
b - slope of fitted straight line
sigmab - standard deviation of b
r - linear correlation coefficient
subroutines and function subprograms required
none