diff options
Diffstat (limited to 'getPeak.m')
| -rw-r--r-- | getPeak.m | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/getPeak.m b/getPeak.m new file mode 100644 index 0000000..088a9ca --- /dev/null +++ b/getPeak.m @@ -0,0 +1,42 @@ +function [fwhm, absorption_min] = getPeak(detunings, absorptions) + + eit_data = [detunings, absorptions]; + + %Get local extrema values and indexes and sort them + [maxima, max_index, minima, min_index] = extrema(eit_data(:,2)); + minima = [min_index, minima]; + maxima = [max_index, maxima]; + + peaks = sortrows([maxima; minima], 1); + + % Find the set of extrema closest to being centered on 0 + center_index = find(eit_data(:,1) == 0); + differences = abs(peaks(:,1) - center_index); + [detuning_index_offset, peak_center_index] = min(differences); + peak_center = peaks(peak_center_index, :); + left_max = peaks(peak_center_index - 1, :); + right_max = peaks(peak_center_index + 1, :); + + %Define each point of interest + absorption_min = peak_center(2); + left_range = left_max(1):peak_center(1); + right_range = peak_center(1):right_max(1); + + %Calculate the width + absorption_max = min([right_max(2), left_max(2)]); % use the smallest of the maximums + absorption_mid = (absorption_max + absorption_min) / 2; + half_width_right = interp1(eit_data(right_range,2), eit_data(right_range,1), absorption_mid) - eit_data(peak_center(1),1); + half_width_left = eit_data(peak_center(1),1) - interp1(eit_data(left_range,2), eit_data(left_range,1), absorption_mid); + fwhm = half_width_right + half_width_left; + + + %Plot extrema over existing plot + % plot(eit_data(:,1), eit_data(:,2)); + % hold all + % grid on + % plot(detuning_1(left_max(1)), left_max(2), 'r*') + % plot(detuning_1(right_max(1)), right_max(2), 'r*') + % plot(detuning_1(peak_center(1)), peak_center(2), 'g*') + + +end |