| Geant4 Cross Reference |
1 /* polevl.c 1
2 * p1evl.c
3 *
4 * Evaluate polynomial
5 *
6 *
7 * SYNOPSIS:
8 *
9 * int N;
10 * double x, y, coef[N+1], nf_polevl[];
11 *
12 * y = nf_polevl( x, coef, N );
13 *
14 *
15 * DESCRIPTION:
16 *
17 * Evaluates polynomial of degree N:
18 *
19 * 2 N
20 * y = C + C x + C x +...+ C x
21 * 0 1 2 N
22 *
23 * Coefficients are stored in reverse order:
24 *
25 * coef[0] = C , ..., coef[N] = C .
26 * N 0
27 *
28 * The function p1evl() assumes that coef[N]
29 * omitted from the array. Its calling argume
30 * otherwise the same as nf_polevl().
31 *
32 */
33
34 /*
35 Cephes Math Library Release 2.1: December, 19
36 Copyright 1984, 1987, 1988 by Stephen L. Moshi
37 Direct inquiries to 30 Frost Street, Cambridge
38 */
39 #include "nf_specialFunctions.h"
40
41 #if defined __cplusplus
42 namespace GIDI {
43 using namespace GIDI;
44 #endif
45
46 double nf_polevl( double x, double coef[], int
47
48 double ans;
49 int i;
50 double *p;
51
52 p = coef;
53 ans = *p++;
54 i = N;
55
56 do {
57 ans = ans * x + *p++; }
58 while( --i ); // Loop checking, 11.06.2015
59
60 return( ans );
61 }
62
63 /*
64 **********************************************
65 */
66 /* Evaluate polynomial when coefficient of x^N
67 double nf_p1evl( double x, double coef[], int
68
69 double ans;
70 double *p;
71 int i;
72
73 p = coef;
74 ans = x + *p++;
75 i = N-1;
76
77 do {
78 ans = ans * x + *p++; }
79 while( --i ); // Loop checking, 11.06.2015
80
81 return( ans );
82 }
83
84 #if defined __cplusplus
85 }
86 #endif
87