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+% Grant David Meadors
+% contrastBeforeAfterRealImaginary
+% g m e a d o r s @ u m i c h . e d u
+% 02012-11-19 (JD 2456251)
+% Plots the calibrated amplitude of Hann
+% windows for Hoft, both before and after feedforward
+
+beforeRaw = load('S6H1_Hann_40_2000test_bins.txt');
+afterRaw = load('S6H1_Hann_40_2000feedforward_bins.txt');
+
+% Each file now is  loaded as a matrix, formatted by column:
+% SFTnumber Frequency(Hz) rawPower calibratedAmplitude scalefactor timebaseline
+% Our object is to average all the calibrated amplitude rows corresponding
+% to a given SFT number.
+
+beforeL = unique(beforeRaw(:,1));
+afterL = unique(afterRaw(:,1));
+
+before = ones(size(beforeL));
+after = ones(size(afterL));
+% Average over all the bins corresponding to a given SFT number,
+% then multiply by sqrt(8/3) because of the Hann window normalization factor.
+for ii = 1:length(before)
+    before(ii) = sqrt(8/3) * mean(beforeRaw(beforeRaw(:,1) == ii, 4));
+end
+for ii = 1:length(after)
+    after(ii) = sqrt(8/3) * mean(afterRaw(afterRaw(:,1) == ii, 4));
+end
+
+figure(1)
+semilogy(beforeL, before,afterL, after)
+legend('Before feedforward', 'After feedforward')
+title('Hann power component vs SFT number for 563 1/1800 bins centered at 850 Hz')
+ylabel('SFT calibrated units, Hoft, amplitude')
+xlabel('SFT number')
+grid on
+print('-dpdf', 'HannAmp.pdf')
+print('-dpng', 'HannAmp.png')
+close(1)
+
+difference = before-after;
+differenceClean = difference;
+differenceClean(isnan(difference)) = [];
+arithmean = mean(differenceClean)*ones(size(difference));
+arithmeanString = horzcat('Arithmetic mean of difference: ', num2str(arithmean(1)));
+
+figure(2)
+plot(beforeL, difference, beforeL, arithmean)
+legend('Before minus after feedforward', arithmeanString)
+xlabel('SFT number')
+ylabel('SFT calibrated units, Hoft, amplitude (before - after)')
+title({'Hann amplitude difference vs SFT number for 563 1/1800 bins centered at 850 Hz';...
+    arithmeanString;...
+    horzcat('Median of difference: ', num2str(median(differenceClean)))});
+grid on
+ylim([-1e-24 1e-24])
+print('-dpdf', 'HannAmpDiff.pdf')
+print('-dpng', 'HannAmpDiff.png')
+close(2)