Is interpolation faster in Simulink or Matlab?

I have a Simulink program that is compiled. The Simulink program contains a Matlab function where the physics are modelled. For each timestep an interpolation will take place, a length is interpolated to an angle. I have the opportunity to choose whether to implement the interpolation in Simulink or within the Matlab function. What is the best?

I know 'interp1' is slow and that there are faster functions like 'interp1q' or 'interp1qr' in Matlab but that have greater demands for the input.

[Walter Roberson]

Which interpolation technique are you using?

Is it correct that you are using 1D interpolation?

[Marcus Jansson]

Yes, it's an array of lengths and an array of corresponding angles.

[Walter Roberson]

Are you doing linear interpolation or bilinear or cubic or something else? What facilities do you need that are not provided by interp1q ?

[Marcus Jansson]

Linear. I can use interp1q, but I wonder if Simulink is even faster with its interpolation features?

[Walter Roberson]

For equally spaced x, see https://www.mathworks.com/matlabcentral/fileexchange/10286-fast-interpolation

For non-equally spaced x, see https://www.mathworks.com/matlabcentral/fileexchange/8627-fast-linear-interpolation

Answer 1

[Jan]

You can use the compiled Mex version FEX: ScaleTime.