Index: trunk/psastro/src/psastroDemoDump.c
===================================================================
--- trunk/psastro/src/psastroDemoDump.c	(revision 15199)
+++ trunk/psastro/src/psastroDemoDump.c	(revision 15562)
@@ -173,2 +173,22 @@
     return true;
 }
+
+// this function is used for test purposes (-trace psastro.dump 1)
+bool psastroDumpGradients (psArray *gradients, char *filename) {
+
+    FILE *f = fopen (filename, "w");
+
+    for (int i = 0; i < gradients->n; i++) {
+	pmAstromGradient *gradient = gradients->data[i];
+
+	// write out the refstar data
+	fprintf (f, "%d  %f %f   %f %f  %f %f\n", i,
+		 gradient->FP.x, gradient->FP.y, 
+		 gradient->dTPdL.x, gradient->dTPdL.y, 
+		 gradient->dTPdM.x, gradient->dTPdM.y);
+    }
+
+    fclose (f);
+    return true;
+}
+