diff --git a/sin.c b/sin.c
index 4b5eb7e..d1e0b25 100644
--- a/sin.c
+++ b/sin.c
@@ -68,7 +68,7 @@ int trig(double theta, double *xy, double *dxy)
 
     xy[0] = x0;
     xy[1] = y0;
-    while (i < 100 && fabs(alpha) > 1e-16)
+    for (i = 0; i < 56; i++)
     {
         d = alpha > 0 ? 1 : (alpha < 0 ? -1 : 0);
         dxy[0] = -d * xy[1] * t;
@@ -76,7 +76,6 @@ int trig(double theta, double *xy, double *dxy)
         xy[0] += dxy[0];
         xy[1] += dxy[1];
         alpha -= d * atanlist[i];
-        i++;
         t /= 2.0;
     }
     return i;
@@ -124,7 +123,7 @@ double sin11(double theta, int *it, double *dsin)
     xy[0] = x0;
     xy[1] = y0;
     dxy[1] = 1;
-    while (i < 100 && fabs(dxy[1]) > 1e-16)
+    for (i = 0; i < 56; i++)
     {
         d = alpha > 0 ? 1 : (alpha < 0 ? -1 : 0);
         dxy[0] = -d * xy[1] * t;
@@ -132,7 +131,6 @@ double sin11(double theta, int *it, double *dsin)
         xy[0] += dxy[0];
         xy[1] += dxy[1];
         alpha -= d * atanlist[i];
-        i++;
         t /= 2.0;
     }
     *dsin = dxy[1];