blob: bbb30cda141b7353f2473eedbf9ae9425a6431ca (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
|
/* determine small t */
#ifndef lint
static const char SCCSID[]="@(#)pj_tsfn.c 4.3 93/06/12 GIE REL";
#endif
#include <math.h>
#include <projects.h>
#define HALFPI 1.5707963267948966
double
pj_tsfn(double phi, double sinphi, double e) {
sinphi *= e;
return (tan (.5 * (HALFPI - phi)) /
pow((1. - sinphi) / (1. + sinphi), .5 * e));
}
|
