modeling with 2 independent variables

I am attempting to use matlab to model a dataset given in 2 columns, temperature and distance, where every 193 rows corresponds to 1 time interval

(i.e. the first column is distance and second is temp with the first 193 rows being t1, the next 193 rows being t2, and so on).

I need to model it such that I have a function of temperature in the form T(d,t). I am struggling on figuring out how to extract the time information from the dataset in order to create a fit. Any help is appreciated

Answer 1

[Star Strider]

If you know what the times are, create a time vector of them using the repmat function (or repelem function, introduced in R2015a). For example, if the times go from 0 to 5, and there are 4 of them (rather than 193), creating the time vector would go somthing like this:

time = 1:5;
repeats = 4;

tv1 = reshape(repmat(time, repeats, 1), [], 1)

tv1 = 20×1

1 1 1 1 2 2 2 2 3 3

tv2 = repelem(time, repeats).'

tv2 = 20×1

1 1 1 1 2 2 2 2 3 3

You can then use that as the time vector in your linear or nonlinear regression.

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[Daniel Fiedorek]

Thank You!

[Star Strider]

As always, my pleasure!

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