A Guide on Spectral Methods Applied to Discrete Data in One Dimension

Figure 5

Calculating the derivative of . (a) displays the original function (gray), the windowed function (black), and the sample points. The dashed line defines the window function. In (b), the analytic (gray line) and estimated numeric (points) derivative is shown. The crosses indicate the result of the calculation without utilizing the window function. Note that some crosses are vertically outside the window for and .

(a)

(b)