Calculating TDEV

The code reproduced in appendix B.1 inputs the time error data from a file produced by SPW. It calculates TDEV via the equation (4.4) reproduced below.

$$TDEV(\tau)=\sqrt{\frac{1}{6n^{2}(N-3n+1)}\sum_{j=1}^{N-3n+1}... ...m_{i=j}^{n+j-1}\left(x_{i+2n}-2x_{i+n}+x_{i}\right)\right)^{2}}$$

where x_i is the i^th sample of the time error function; N is the total number of samples; $\tau=n\tau_0$ is the integration time; and $n=1,2,\ldots,$ $\mathrm{int}(\frac{N}{3})$ is the number of sampling intervals.
The TDEV data is written to file so that it may be plotted using MATLAB.

The source code is reproduced in appendix B.1.