Many geophysical map estimation problems appear to be multidimensional,
but actually they are not.
To see the tip of the iceberg, consider this example:
On a two-dimensional cartesian mesh, the function
has the autocorrelation
.
Likewise, on a one-dimensional cartesian mesh,
the function
has the autocorrelation
.
Observe the numbers in the one-dimensional world are identical
with the numbers in the two-dimensional world.
This correspondence is no accident.