Accession Number : AD0255714

Title :   SIMULTANEOUS LEAST-SQUARES APPROXIMATION OF A FUNCTION AND ITS FIRST INTEGRALS WITH APPLICATION TO THERMODYNAMIC DATA

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON D C

Personal Author(s) : ZELEZNIK,FRANK J. ; GORDON,SANFORD

Report Date : MAY 1961

Pagination or Media Count : 1

Abstract : A method is presented for the simultaneous leastsquares approximation of a function and its first integrals subject to the constraint that the re iduals vanish at some point in the interval of the fit. This method is applied to fitting empirical equations to the thermodynamic functions heat capacity, enthalpy, and entropy. Numerical examples indicate, first, that on the basis of the residuals in all the functions a simultaneous fit is superior to fitting heat capacity alone, and second, that no one form of the empirical equation can be considered best for all chemical species over any arbitrary temperature interval. (Author)

Descriptors :   *FUNCTIONS(MATHEMATICS), *LEAST SQUARES METHOD, *NUMERICAL ANALYSIS, *THERMODYNAMICS, ENTHALPY, ENTROPY, EQUATIONS, INTEGRALS

Distribution Statement : APPROVED FOR PUBLIC RELEASE