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authorEven Rouault <even.rouault@spatialys.com>2018-12-18 20:24:11 +0100
committerEven Rouault <even.rouault@spatialys.com>2018-12-26 10:08:53 +0100
commit610957f7035242f15743c399ffd429b92bc36206 (patch)
tree73f0d51147e2f4860c4bfc875f7a4bf9359386d4 /src/pj_phi2.c
parent355d681ed88019e97742344bd642c2fd97e700a1 (diff)
downloadPROJ-610957f7035242f15743c399ffd429b92bc36206.tar.gz
PROJ-610957f7035242f15743c399ffd429b92bc36206.zip
cpp conversion: minimal steps to fix compilation errors, not warnings
Diffstat (limited to 'src/pj_phi2.c')
-rw-r--r--src/pj_phi2.c46
1 files changed, 0 insertions, 46 deletions
diff --git a/src/pj_phi2.c b/src/pj_phi2.c
deleted file mode 100644
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--- a/src/pj_phi2.c
+++ /dev/null
@@ -1,46 +0,0 @@
-/* Determine latitude angle phi-2. */
-
-#include <math.h>
-
-#include "projects.h"
-
-static const double TOL = 1.0e-10;
-static const int N_ITER = 15;
-
-/*****************************************************************************/
-double pj_phi2(projCtx ctx, double ts, double e) {
-/******************************************************************************
-Determine latitude angle phi-2.
-Inputs:
- ts = exp(-psi) where psi is the isometric latitude (dimensionless)
- e = eccentricity of the ellipsoid (dimensionless)
-Output:
- phi = geographic latitude (radians)
-Here isometric latitude is defined by
- psi = log( tan(pi/4 + phi/2) *
- ( (1 - e*sin(phi)) / (1 + e*sin(phi)) )^(e/2) )
- = asinh(tan(phi)) - e * atanh(e * sin(phi))
-This routine inverts this relation using the iterative scheme given
-by Snyder (1987), Eqs. (7-9) - (7-11)
-*******************************************************************************/
- double eccnth = .5 * e;
- double Phi = M_HALFPI - 2. * atan(ts);
- double con;
- int i = N_ITER;
-
- for(;;) {
- double dphi;
- con = e * sin(Phi);
- dphi = M_HALFPI - 2. * atan(ts * pow((1. - con) /
- (1. + con), eccnth)) - Phi;
-
- Phi += dphi;
-
- if (fabs(dphi) > TOL && --i)
- continue;
- break;
- }
- if (i <= 0)
- pj_ctx_set_errno(ctx, PJD_ERR_NON_CON_INV_PHI2);
- return Phi;
-}