On Jun 18, 2007, at 1:28 PM, Giovanni A. Cignoni wrote:

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The main change to the DTD is addition of 'discrete' as asupported interpolation method for tabular data, yielding a stair-step response from such a function. This came from a suggestionfrom Geoff Brian of Australia's DSTO."Discrete" interpolation is the method also known as "nearestneighbor"?Being x in [a, b], f(x) is f(a) or f(b) depending on x being nearerto a or b. Correct?Thanks in advance, ciao, Giovanni Cignoni.

`This is a good question, Giovanni. I see that we need to be much more`

`rigorous in our definition of 'discrete' as it applies to these tables.`

`I had assumed the interpretation would be as follows (I don't think`

`this is 'nearest-neighbor')...`

`In the case of a one-dimensional function, if the independentVarPts`

`are defined as`

[a, b, c, d] and an arbitrary griddedTable points are defined as [8.5, 9.0, 9.5, 10.0] the function f(x) would be evaluated as shown below: f(x) ^ | 10.0 - | o | | | | 9.5 - | o------o | | | | 9.0 - | o------o | | | | 8.5 - | o------o | |----------------------------------> X | | | | a b c d so the independent values state where the function changes value.

`Nearest-neighbor would put the transitions exactly between the`

`independent break points.`

`I'd appreciate any feedback on this topic, especially from Geoff`

`Brian who is apparently making use of this 'extension' to DAVE-ML.`

-- Bruce