Improve error message

Author: Tara Drwenski

cdm/core/src/main/java/ucar/nc2/ft2/coverage/CoordAxisHelper.java

@@ -100,11 +100,11 @@ private int findCoordElementRegular(double coordValue, boolean bounded) {
       double lower = axis.getCoordEdge1(index);
       double upper = axis.getCoordEdge2(index);
       if (axis.isAscending()) {
-        assert lower <= coordValue : lower + " should be le " + coordValue;
-        assert upper >= coordValue : upper + " should be ge " + coordValue;
+        assert lower <= coordValue : lower + " should be <= " + coordValue;
+        assert upper >= coordValue : upper + " should be >= " + coordValue;
       } else {
-        assert lower >= coordValue : lower + " should be ge " + coordValue;
-        assert upper <= coordValue : upper + " should be le " + coordValue;
+        assert lower >= coordValue : lower + " should be >= " + coordValue;
+        assert upper <= coordValue : upper + " should be <= " + coordValue;
       }
     }