Data Sampling and Interpolation

Using a simple cosine wave as an example, this Demonstration shows how the number of data points and the interpolation order affect the resulting interpolating function. The blue line represents the plot of the interpolating function, the red line represents the numerical difference between the interpolating function values and the true values of the sinusoid, and the black points are the points used in the interpolation. The sampling rate corresponds to the number of sample points per oscillation.