Index: /issm/trunk-jpl/src/c/classes/kriging/Observations.cpp
===================================================================
--- /issm/trunk-jpl/src/c/classes/kriging/Observations.cpp	(revision 19155)
+++ /issm/trunk-jpl/src/c/classes/kriging/Observations.cpp	(revision 19156)
@@ -155,5 +155,4 @@
 
 	/*Intermediaries*/
-    int          maxdepth = 20;
 	 IssmPDouble  minspacing,mintrimming,maxtrimming;
 
@@ -166,4 +165,23 @@
 	options->Get(&minspacing,"minspacing",0.01);
 	if(minspacing<=0) _error_("minspacing must > 0");
+
+	/*Get maximum distance between 2 points
+	 *  maxDist should be the maximum distance that any two points
+	 *  can have between each other. IE p.distance(q) < maxDist for all
+	 *  p,q that you will ever try to insert. The cover tree may be invalid
+	 *  if an inaccurate maxDist is given.*/
+	IssmPDouble xmin = x[0];
+	IssmPDouble xmax = x[0];
+	IssmPDouble ymin = y[0];
+	IssmPDouble ymax = y[0];
+	for(int i=1;i<n;i++){
+		if(x[i]<xmin) xmin=x[i];
+		if(x[i]>xmax) xmax=x[i];
+		if(y[i]<ymin) ymin=y[i];
+		if(y[i]>ymax) ymax=y[i];
+	}
+	IssmPDouble maxDist = sqrt(pow(xmax-xmin,2)+pow(ymax-ymin,2));
+	IssmPDouble base    = 2.;
+	int         maxdepth = ceilf(log(maxDist)/log(base));
 
 	 _printf0_("Generating covertree with a maximum depth " <<  maxdepth <<"... ");
@@ -534,4 +552,5 @@
 	/*First: Create semivariogram matrix for observations*/
 	for(i=0;i<n_obs;i++){
+		//printf("%g %g ==> %g\n",x[i],y[i],sqrt(pow(x[i]-x_interp,2)+pow(y[i]-y_interp,2)));
 		for(j=0;j<=i;j++){
 			A[i*(n_obs+1)+j] = variogram->Covariance(x[i]-x[j],y[i]-y[j]);