Solution of the wave equation in 1 space dimension (vibrating string). The user can specify the initial condition (initial shape of the string) by entering the function in an input box, or by choosing an example from a drop-down menu. The initial velocity is [math]0[/math], and the string is fixed at the endpoints.
The Fourier coefficients of the initial condition are approximated through a discrete Fourier transform (DFT) and the solution is computed by separation of variables.
[b]Technical comment: [/b] The DFT and its inverse are computed in JavaScript (directly from the definition: no FFT!).
The same result could be achieved (in an even simpler way) by using list commands...but the resulting applet is slow as hell on tablets and phones!
