# SasView/sasmodels

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 /* polevl.c * p1evl.c * * Evaluate polynomial * * * * SYNOPSIS: * * int N; * double x, y, coef[N+1], polevl[]; * * y = polevl( x, coef, N ); * * * * DESCRIPTION: * * Evaluates polynomial of degree N: * * 2 N * y = C + C x + C x +...+ C x * 0 1 2 N * * Coefficients are stored in reverse order: * * coef[0] = C , ..., coef[N] = C . * N 0 * * The function p1evl() assumes that C_N = 1.0 and is * omitted from the array. Its calling arguments are * otherwise the same as polevl(). * * * SPEED: * * In the interest of speed, there are no checks for out * of bounds arithmetic. This routine is used by most of * the functions in the library. Depending on available * equipment features, the user may wish to rewrite the * program in microcode or assembly language. * */ /* Cephes Math Library Release 2.1: December, 1988 Copyright 1984, 1987, 1988 by Stephen L. Moshier Direct inquiries to 30 Frost Street, Cambridge, MA 02140 */ double polevl( double x, constant double *coef, int N ); double polevl( double x, constant double *coef, int N ) { int i = 0; double ans = coef[i]; while (i < N) { i++; ans = ans * x + coef[i]; } return ans; } /* p1evl() */ /* N * Evaluate polynomial when coefficient of x is 1.0. * Otherwise same as polevl. */ double p1evl( double x, constant double *coef, int N ); double p1evl( double x, constant double *coef, int N ) { int i=0; double ans = x+coef[i]; while (i < N-1) { i++; ans = ans*x + coef[i]; } return ans; }