diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/pj_qsfn.c | 24 |
1 files changed, 15 insertions, 9 deletions
diff --git a/src/pj_qsfn.c b/src/pj_qsfn.c index ccb12308..c3610140 100644 --- a/src/pj_qsfn.c +++ b/src/pj_qsfn.c @@ -3,14 +3,20 @@ #include <projects.h> # define EPSILON 1.0e-7 - double -pj_qsfn(double sinphi, double e, double one_es) { - double con; - if (e >= EPSILON) { - con = e * sinphi; - return (one_es * (sinphi / (1. - con * con) - - (.5 / e) * log ((1. - con) / (1. + con)))); - } else - return (sinphi + sinphi); +double pj_qsfn(double sinphi, double e, double one_es) { + double con, div1, div2; + + if (e >= EPSILON) { + con = e * sinphi; + div1 = 1.0 - con * con; + div2 = 1.0 + con; + + /* avoid zero division, fail gracefully */ + if (div1 == 0.0 || div2 == 0.0) + return HUGE_VAL; + + return (one_es * (sinphi / div1 - (.5 / e) * log ((1. - con) / div2 ))); + } else + return (sinphi + sinphi); } |