Multivariable data lookup and interpolation

[geo_curious]

Hi,

I am trying to import data from a properties spreadsheet for grout mixes. This properties sheet has nothing to do with a timeseries. I believe the correct function to use would be GET XLSX CONSTANTS(). I do not see a way to load this as a .dat or .vdfx because there is no timeseries. Unfortunately, GET XLSX CONSTANTS() does not seem to be working with the spreadsheet (shown).

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I get a syntax error when attempting to save the variable.

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After I figure out how to import the data, I would like a multivariable interpolation of the density, shown as the last column in image 1.
Most of the data handling information surrounds the use of timeseries, or simple 2 variable lookups, as I have seen in documentation. Could you please direct me as to how to tackle this problem?

In short:
I want to import data to interpolate a single value from, based on multiple variable settings in Vensim, as represented by column values in a properties spreadsheet.

[tomfid]

You have a syntax problem - '1' is not a valid cell reference.
https://www.vensim.com/documentation/fn ... tants.html

Not sure what you have in mind for interpolation. You have 4 inputs, but since they have to sum to 100%, it looks like a 3D space. I'm not sure there's a general procedure for a 3D lookup, especially if the known points cover the space sparsely. I'd probably try some kind of radial basis function first.

However, calculating density doesn't strike me as a case for interpolation, because the physics are known explicitly.

Density = SUM( componentDensity[k!]*componentQuantity[k!] )/SUM( componentQuantity[k!] )
or
=SUM( componentMass[k!] )/SUM( componentMass[k!]/componentDensity[k!] )
A units check will see if I got this right off the top of my head.

This doesn't quite work if there are nonlinear interactions (e.g., phase changes, foaming, etc.) but that seems unlikely for mortar.