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Re: Contour lines, etc.

On Mon, 5 May 97 LUDWIK KOWALSKI wrote:

... Creating a contour plot map is trivial (I wrote my own program for
this yesterday) when a complete set of data is available, that is when
a value of Z is assigned to every possible x,y location.

This is not true. Interpolational ambiguities also exist after a value of
Z is assigned to every possible mesh point. The origin of data (formulas
versus a measurements) is no longer significant at this point. Here is an
illustration.

Suppose we want a contour plot for potentials between Z1=100 and Z2=101.
(A range of Z must be given to define a contour line. Keep in mind that
a too narrow range may miss all data). Cells populated with a chosen
range will not not always be adjacent mesh cells. In fact two points
belonging to a single contour line can be separated by numerous cells
belonging to other contour lines. Pattern recognition dilemmas must be
always solved to avoid misinterpretations. Can this be done without
introducing large errors?