find the function that links some input data to some output data

hello expert ,

i'm working in a code in Matlab , i inter some values x and the programme returns me other values y . i want to know the function that link the x to the y how can i get it .

i will be thankful for you

[Stephen23]

There are infinite functions that exactly describe any finite set of data points, so you will have to be much more specific with your request. Basically you have a choice between:

1. using prior knowledge to fit a specific function, or
2. fitting the data with a spline or something similar.

Which would you prefer? Do you know anything about the underlying physical models that describe the behavior of the data?

[Star Strider]

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