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
|
double form_volume(double length, double kuhn_length, double radius);
double Iq(double q, double length, double kuhn_length, double radius,
double axis_ratio, double sld, double solvent_sld);
double flexible_cylinder_ex_kernel(double q, double length, double kuhn_length,
double radius, double axis_ratio, double sld,
double solvent_sld);
double elliptical_crosssection(double q, double a, double b);
double form_volume(double length, double kuhn_length, double radius)
{
return 1.0;
}
double
elliptical_crosssection(double q, double a, double b)
{
double sum=0.0;
for(int i=0;i<GAUSS_N;i++) {
const double zi = ( GAUSS_Z[i] + 1.0 )*M_PI_4;
double sn, cn;
SINCOS(zi, sn, cn);
const double arg = q*sqrt(a*a*sn*sn + b*b*cn*cn);
const double yyy = sas_2J1x_x(arg);
sum += GAUSS_W[i] * yyy * yyy;
}
sum *= 0.5;
return(sum);
}
double flexible_cylinder_ex_kernel(double q,
double length,
double kuhn_length,
double radius,
double axis_ratio,
double sld,
double solvent_sld)
{
double flex,crossSect, cont;
cont = sld - solvent_sld;
crossSect = elliptical_crosssection(q,radius,(radius*axis_ratio));
flex = Sk_WR(q,length,kuhn_length);
flex *= crossSect;
flex *= M_PI*radius*radius*axis_ratio*axis_ratio*length;
flex *= cont*cont;
flex *= 1.0e-4;
return flex;
}
double Iq(double q,
double length,
double kuhn_length,
double radius,
double axis_ratio,
double sld,
double solvent_sld)
{
double result = flexible_cylinder_ex_kernel(q,
length,
kuhn_length,
radius,
axis_ratio,
sld,
solvent_sld);
return result;
}
|
