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| author | Frank Warmerdam <warmerdam@pobox.com> | 1999-03-18 16:34:52 +0000 |
|---|---|---|
| committer | Frank Warmerdam <warmerdam@pobox.com> | 1999-03-18 16:34:52 +0000 |
| commit | 565a4bd035b9d4a83955808efef20f1d8dfa24cf (patch) | |
| tree | 75785fc897708023f1ccdaf40079afcbaaf0fd3a /src/PJ_putp2.c | |
| download | PROJ-565a4bd035b9d4a83955808efef20f1d8dfa24cf.tar.gz PROJ-565a4bd035b9d4a83955808efef20f1d8dfa24cf.zip | |
New
git-svn-id: http://svn.osgeo.org/metacrs/proj/trunk@776 4e78687f-474d-0410-85f9-8d5e500ac6b2
Diffstat (limited to 'src/PJ_putp2.c')
| -rw-r--r-- | src/PJ_putp2.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/src/PJ_putp2.c b/src/PJ_putp2.c new file mode 100644 index 00000000..89ec6720 --- /dev/null +++ b/src/PJ_putp2.c @@ -0,0 +1,43 @@ +#ifndef lint +static const char SCCSID[]="@(#)PJ_putp2.c 4.1 94/02/15 GIE REL"; +#endif +#define PJ_LIB__ +#include <projects.h> +PROJ_HEAD(putp2, "Putnins P2") "\n\tPCyl., Sph."; +#define C_x 1.89490 +#define C_y 1.71848 +#define C_p 0.6141848493043784 +#define EPS 1e-10 +#define NITER 10 +#define PI_DIV_3 1.0471975511965977 +FORWARD(s_forward); /* spheroid */ + double p, c, s, V; + int i; + + p = C_p * sin(lp.phi); + s = lp.phi * lp.phi; + lp.phi *= 0.615709 + s * ( 0.00909953 + s * 0.0046292 ); + for (i = NITER; i ; --i) { + c = cos(lp.phi); + s = sin(lp.phi); + lp.phi -= V = (lp.phi + s * (c - 1.) - p) / + (1. + c * (c - 1.) - s * s); + if (fabs(V) < EPS) + break; + } + if (!i) + lp.phi = lp.phi < 0 ? - PI_DIV_3 : PI_DIV_3; + xy.x = C_x * lp.lam * (cos(lp.phi) - 0.5); + xy.y = C_y * sin(lp.phi); + return (xy); +} +INVERSE(s_inverse); /* spheroid */ + double c; + + lp.phi = aasin(xy.y / C_y); + lp.lam = xy.x / (C_x * ((c = cos(lp.phi)) - 0.5)); + lp.phi = aasin((lp.phi + sin(lp.phi) * (c - 1.)) / C_p); + return (lp); +} +FREEUP; if (P) pj_dalloc(P); } +ENTRY0(putp2) P->es = 0.; P->inv = s_inverse; P->fwd = s_forward; ENDENTRY(P) |