1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
/* simpsn.c */
/* simpsn.c
* Numerical integration of function tabulated
* at equally spaced arguments
*/
/* Coefficients for Cote integration formulas */
/* Note: these numbers were computed using 40-decimal precision. */
#define NCOTE 8
/* 6th order formula */
/*
static double simcon[] =
{
4.88095238095238095E-2,
2.57142857142857142857E-1,
3.2142857142857142857E-2,
3.2380952380952380952E-1,
};
*/
/* 8th order formula */
static double simcon[] =
{
3.488536155202821869E-2,
2.076895943562610229E-1,
-3.27336860670194003527E-2,
3.7022927689594356261E-1,
-1.6014109347442680776E-1,
};
/* 10th order formula */
/*
static double simcon[] =
{
2.68341483619261397039E-2,
1.77535941424830313719E-1,
-8.1043570626903960237E-2,
4.5494628827962161295E-1,
-4.3515512265512265512E-1,
7.1376463043129709796E-1,
};
*/
/* simpsn.c 2 */
/* 20th order formula */
/*
static double simcon[] =
{
1.182527324903160319E-2,
1.14137717644606974987E-1,
-2.36478370511426964E-1,
1.20618689348187566E+0,
-3.7710317267153304677E+0,
1.03367982199398011435E+1,
-2.270881584397951229796E+1,
4.1828057422193554603E+1,
-6.4075279490154004651555E+1,
8.279728347247285172085E+1,
-9.0005367135242894657916E+1,
};
*/
/* simpsn.c 3 */
double simpsn( f, delta )
double f[]; /* tabulated function */
double delta; /* spacing of arguments */
{
extern double simcon[];
double ans;
int i;
ans = simcon[NCOTE/2] * f[NCOTE/2];
for( i=0; i < NCOTE/2; i++ )
ans += simcon[i] * ( f[i] + f[NCOTE-i] );
return( ans * delta * NCOTE );
}
|
