Index: trunk/psphot/src/psPolynomials.c
===================================================================
--- trunk/psphot/src/psPolynomials.c	(revision 4116)
+++ trunk/psphot/src/psPolynomials.c	(revision 4129)
@@ -233,5 +233,5 @@
     // Build the B and A data structs.
     for (int k = 0; k < x->n; k++) {
-        if ((mask != NULL) && mask->U8[k]) continue;
+        if ((mask != NULL) && mask->data.U8[k]) continue;
 	xSums = BuildSums1D(xSums, x->data.F64[k], nTerm);
       
@@ -325,5 +325,5 @@
     // Build the B and A data structs.
     for (int k  = 0; k < x->n; k++) {
-      if ((mask != NULL) && mask->data.U8[i]) continue;
+      if ((mask != NULL) && mask->data.U8[k]) continue;
 	Sums = BuildSums2D(Sums, x->data.F64[k], y->data.F64[k], nXterm, nYterm);