Index: trunk/psastro/src/psastroAstromGuess.c
===================================================================
--- trunk/psastro/src/psastroAstromGuess.c	(revision 23844)
+++ trunk/psastro/src/psastroAstromGuess.c	(revision 23989)
@@ -382,6 +382,12 @@
     psStats *statsQ = psStatsAlloc (PS_STAT_SAMPLE_MEAN | PS_STAT_SAMPLE_STDEV);
 
-    psVectorStats (statsP, cornerPd, NULL, cornerMK, 1);
-    psVectorStats (statsQ, cornerQd, NULL, cornerMK, 1);
+    if (!psVectorStats (statsP, cornerPd, NULL, cornerMK, 1)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return false;
+    }
+    if (!psVectorStats (statsQ, cornerQd, NULL, cornerMK, 1)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return false;
+    }
 
     float angle = atan2 (map->y->coeff[1][0], map->x->coeff[1][0]);
Index: trunk/psastro/src/psastroFixChipsTest.c
===================================================================
--- trunk/psastro/src/psastroFixChipsTest.c	(revision 23844)
+++ trunk/psastro/src/psastroFixChipsTest.c	(revision 23989)
@@ -140,5 +140,8 @@
     psStats *stats;
     stats = psStatsAlloc (PS_STAT_ROBUST_MEDIAN | PS_STAT_ROBUST_STDEV);
-    psVectorStats (stats, dX, NULL, NULL, 0);
+    if (!psVectorStats (stats, dX, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return false;
+    }
     Xo = stats->robustMedian;
     fprintf (stderr, "offset x: %f +/- %f\n", stats->robustMedian, stats->robustStdev);
@@ -146,5 +149,8 @@
 
     stats = psStatsAlloc (PS_STAT_ROBUST_MEDIAN | PS_STAT_ROBUST_STDEV);
-    psVectorStats (stats, dY, NULL, NULL, 0);
+    if (!psVectorStats (stats, dY, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return false;
+    }
     Yo = stats->robustMedian;
     fprintf (stderr, "offset y: %f +/- %f\n", stats->robustMedian, stats->robustStdev);
@@ -168,5 +174,8 @@
     }
     stats = psStatsAlloc (PS_STAT_ROBUST_MEDIAN | PS_STAT_ROBUST_STDEV);
-    psVectorStats (stats, dT, NULL, NULL, 0);
+    if (!psVectorStats (stats, dT, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return false;
+    }
     float To = stats->robustMedian;
     fprintf (stderr, "offset t: %f +/- %f\n", stats->robustMedian, stats->robustStdev);
Index: trunk/psastro/src/psastroModelAnalysis.c
===================================================================
--- trunk/psastro/src/psastroModelAnalysis.c	(revision 23844)
+++ trunk/psastro/src/psastroModelAnalysis.c	(revision 23989)
@@ -153,5 +153,8 @@
 
     psStats *stats = psStatsAlloc (PS_STAT_SAMPLE_MEDIAN | PS_STAT_SAMPLE_STDEV);
-    psVectorStats (stats, posZero, NULL, NULL, 0);
+    if (!psVectorStats (stats, posZero, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return false;
+    }
 
     fprintf (outfile, "# pos zero %f +/- %f\n", stats->sampleMedian, stats->sampleStdev);
Index: trunk/psastro/src/psastroModelFitBoresite.c
===================================================================
--- trunk/psastro/src/psastroModelFitBoresite.c	(revision 23844)
+++ trunk/psastro/src/psastroModelFitBoresite.c	(revision 23989)
@@ -62,10 +62,16 @@
 
     // center (Xo) = mean(Xo), RX = range / 2
-    psVectorStats (stats, Xo, NULL, NULL, 0);
+    if (!psVectorStats (stats, Xo, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return NULL;
+    }
     params->data.F32[PAR_X0] = stats->sampleMean;
     params->data.F32[PAR_RX] = (stats->max - stats->min) / 2.0;
 
     // center (Yo) = mean(Yo), RY = range / 2
-    psVectorStats (stats, Yo, NULL, NULL, 0);
+    if (!psVectorStats (stats, Yo, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return NULL;
+    }
     params->data.F32[PAR_Y0] = stats->sampleMean;
     params->data.F32[PAR_RY] = (stats->max - stats->min) / 2.0;
Index: trunk/psastro/src/psastroZeroPoint.c
===================================================================
--- trunk/psastro/src/psastroZeroPoint.c	(revision 23844)
+++ trunk/psastro/src/psastroZeroPoint.c	(revision 23989)
@@ -126,5 +126,8 @@
     // this analysis has too few data points to use the robust median method
     psStats *stats = psStatsAlloc (PS_STAT_CLIPPED_MEAN | PS_STAT_CLIPPED_STDEV);
-    psVectorStats (stats, dMag, NULL, NULL, 0);
+    if (!psVectorStats (stats, dMag, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return false;
+    }
     fprintf (stderr, "zero point %f +/- %f using %d stars; transparency %f\n", stats->clippedMean, stats->clippedStdev, Npts, zeropt - stats->clippedMean);