1 files changed, 1 insertions, 1 deletions
diff --git a/src/PJ_eqdc.c b/src/PJ_eqdc.c
index 917131e1..ce1a8bd8 100644
--- a/src/PJ_eqdc.c
+++ b/src/PJ_eqdc.c
@@ -46,7 +46,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
         lp.lam = atan2(xy.x, xy.y) / Q->n;
     } else {
         lp.lam = 0.;
-        lp.phi = Q->n > 0. ? HALFPI : - HALFPI;
+        lp.phi = Q->n > 0. ? M_HALFPI : -M_HALFPI;
     }
     return lp;
 }