semestralka

semestralka/1.m

@@ -7,26 +7,37 @@ rawText = fileread('data6.dat');
 nums = regexp(rawText, '[-+]?\d+', 'match');
 data = int16(str2double(nums));
 
-X = DFT_priama(double(data))
-n = length(X)
+X = DFT_priama(double(data));
+n = length(X);
 Fs = 200;
-freq = (0:n-1)*Fs/n
+freq = (0:n-1)*Fs/n;
 
 figure;
 plot(double(data));
 figure;
 plot(freq, X)
+%3
 figure;
-x = double(data);
-x = x - mean(x);
-plot(x); % centrovane data
+magX = abs(X);
+plot(freq, magX)
+% freq shift pre -Fs/2 po Fs/2
+freq_shift = (-n/2:n/2-1)*(Fs/n);
+%4
 figure;
-plot(freq, abs(X))
+subplot(2,1,1);
+plot(freq_shift, real(fftshift(X)), 'b');
+subplot(2,1,2);
+plot(freq_shift, imag(fftshift(X)), 'r');
+%5
+figure;
+plot(freq, imag(X), 'r');
+%6
+figure;
+plot(freq, real(X), 'r');
 figure;
 plot(freq, angle(X))
 
-magX = abs(X);
-[pks, locs] = findpeaks(magX, 'NPeaks', 6, 'SortStr', 'descend');
-
-f0 = freq(locs);
-disp(f0);
+[pks, locs] = findpeaks(magX, 'NPeaks', 10, 'SortStr', 'descend');
+f0 = freq(locs)
+f0b = f0(f0 < 100);
+f0_ohranicene = f0b