source: sasmodels/sasmodels/models/star_polymer.c @ d86f0fc

core_shell_microgelsmagnetic_modelticket-1257-vesicle-productticket_1156ticket_1265_superballticket_822_more_unit_tests
Last change on this file since d86f0fc was 2586093f, checked in by Paul Kienzle <pkienzle@…>, 7 years ago

use standard kernel name

  • Property mode set to 100644
File size: 537 bytes
Line 
1double form_volume(void);
2
3double Iq(double q, double radius2, double arms);
4
5static double star_polymer_kernel(double q, double radius2, double arms)
6{
7
8    double u_2 = radius2 * q * q;
9    double v = u_2 * arms / (3.0 * arms - 2.0);
10
11    double term1 = v + expm1(-v);
12    double term2 = ((arms - 1.0)/2.0) * square(expm1(-v));
13
14    return (2.0 * (term1 + term2)) / (arms * v * v);
15
16}
17
18double form_volume(void)
19{
20    return 1.0;
21}
22
23double Iq(double q, double radius2, double arms)
24{
25    return star_polymer_kernel(q, radius2, arms);
26}
Note: See TracBrowser for help on using the repository browser.