new file mode 100644
--- /dev/null
+++ b/volume_io/Testing/create_grid_volume.c
@@ -0,0 +1,61 @@
+#include  <internal_volume_io.h>
+
+#define  X_SIZE   10
+#define  Y_SIZE   10
+#define  Z_SIZE   10
+
+int  main(
+    int   argc,
+    char  *argv[] )
+{
+    Status               status;
+    char                 *output_filename;
+    int                  ind[MAX_DIMENSIONS], sizes[MAX_DIMENSIONS];
+    static  char         *dim_names[] = { MIxspace, MIyspace, MIzspace,
+                                          MIvector_dimension };
+    Real                 value;
+    Volume               volume;
+
+    if( argc < 2 )
+    {
+        print( "Args.\n" );
+        return( 1 );
+    }
+
+    output_filename = argv[1];
+
+    volume = create_volume( 4, dim_names, NC_SHORT, TRUE, 0.0, 0.0 );
+
+    sizes[X] = X_SIZE;
+    sizes[Y] = Y_SIZE;
+    sizes[Z] = Z_SIZE;
+    sizes[Z+1] = 3;
+    set_volume_sizes( volume, sizes );
+
+    set_volume_real_range( volume, -100.0, 100.0 );
+
+    alloc_volume_data( volume );
+
+    for_less( ind[X], 0, sizes[X] )
+    {
+        for_less( ind[Y], 0, sizes[Y] )
+        {
+            for_less( ind[Z], 0, sizes[Z] )
+            {
+                for_less( ind[Z+1], 0, sizes[Z+1] )
+                {
+                    value = (Real) ind[ind[Z+1]] / (Real) sizes[ind[Z+1]];
+                    value = 4.0 * value - 2.0;
+                    value = CONVERT_VALUE_TO_VOXEL( volume, value );
+                    SET_VOXEL( volume, ind[X], ind[Y], ind[Z], ind[Z+1], 0,
+                               value );
+                }
+            }
+        }
+    }
+
+    status = output_volume( output_filename, NC_UNSPECIFIED, FALSE, 0.0, 0.0,
+                            volume, "", NULL );
+
+    return( status != OK );
+}