Application

Let us use the previous display routine on the FFT of the temperature data

TempFreq = fft(centerTemp);
absSpect=abs(fft(centerTemp));
Fs=1/3600;
figure(1);
MinesMagPlotFFT(powerSpect,Fs);

yields

We see a strong spike around 0.1 10^4 Hz (we neglect the spike at 0 Hz). In the next page we are going to detect this spike and its frequency location (and corresponding period).