How can I increase my dataset length by Interpolation?

I want to increase my data set length from say 5571x1 to 5590x1 by interpolating it non linearly since this dataset is experimental and there is no fixed interval.

All i've experimented with is using 'interp' and 'interp1' but no luck so far.

[darova]

PLease show your attempts

Answer 1

[Ameer Hamza]

This is a simple example which interpolates the data using cubic interpolation

x = rand(5571, 1); % your signal

t = linspace(0, 1, numel(x));
n = 5590; % required length
t_ = linspace(0, 1, n);
x_ = interp1(t, x, t_, 'spline').'; % x_ has dimensions of 5590x1

[Sahil Patel]

Thank you! This helped, although 'spline' changed my signal data a bit. Is there a way to interpolate in such a way that existing data isnt changed?

[Ameer Hamza]

You can try 'linear', 'pchip', or 'makima' in place of spline and see which fits your requirement.