1 files changed, 8 insertions, 3 deletions
diff --git a/src/gauss.cpp b/src/gauss.cpp
index b7a27191..49ccfa1c 100644
--- a/src/gauss.cpp
+++ b/src/gauss.cpp
@@ -65,9 +65,14 @@ void *pj_gauss_ini(double e, double phi0, double *chi, double *rc) {
     }
     *chi = asin(sphi / en->C);
     en->ratexp = 0.5 * en->C * e;
-    en->K = tan(.5 * *chi + M_FORTPI) / (
-        pow(tan(.5 * phi0 + M_FORTPI), en->C) *
-        srat(en->e * sphi, en->ratexp)  );
+    if( .5 * phi0 + M_FORTPI < 1e-10 ) {
+        en->K = 1.0 / srat(en->e * sphi, en->ratexp);
+    }
+    else {
+        en->K = tan(.5 * *chi + M_FORTPI) / (
+            pow(tan(.5 * phi0 + M_FORTPI), en->C) *
+            srat(en->e * sphi, en->ratexp)  );
+    }
     return ((void *)en);
 }