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-rw-r--r--src/pj_phi2.c10
1 files changed, 7 insertions, 3 deletions
diff --git a/src/pj_phi2.c b/src/pj_phi2.c
index 60b36ec4..fa6d9950 100644
--- a/src/pj_phi2.c
+++ b/src/pj_phi2.c
@@ -6,18 +6,22 @@
double
pj_phi2(projCtx ctx, double ts, double e) {
- double eccnth, Phi, con, dphi;
+ double eccnth, Phi, con;
int i;
eccnth = .5 * e;
Phi = M_HALFPI - 2. * atan (ts);
i = N_ITER;
- do {
+ for(;;) {
+ double dphi;
con = e * sin (Phi);
dphi = M_HALFPI - 2. * atan (ts * pow((1. - con) /
(1. + con), eccnth)) - Phi;
Phi += dphi;
- } while ( fabs(dphi) > TOL && --i);
+ if( fabs(dphi) > TOL && --i )
+ continue;
+ break;
+ }
if (i <= 0)
pj_ctx_set_errno( ctx, -18 );
return Phi;