FORTRAN programs for data fitting using orthogonal polynomials. [ORFIT, FIT, and TFIT, for PDP-11]

The use of orthogonal functions in least-squares data fitting is discussed, and a FORTRAN subroutine (ORFIT) which uses orthogonal polynomials in data fitting is presented. Also described are two FORTRAN programs for fitting data which use the subroutine ORFIT. The first one, FIT, is a general-purpose data fitting program. The second one, TFIT, is specifically intended for use in calibrating cryogenic germanium resistance thermometers. TFIT fits lnT to a polynomial in lnR (where T and R are the temperature and resistance, respectively).