Added new routine to simulate distribution of data and compute its cumulants, additionally made minor modifications to experimental data analysis routines.

This commit is contained in:
Karthik 2025-08-06 19:06:02 +02:00
parent e0136d4a19
commit 304758bebe
4 changed files with 318 additions and 24 deletions

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@ -160,8 +160,8 @@ for k = 1 : length(files)
(isempty(bkg_img) && isa(bkg_img, 'double')) || ...
(isempty(dark_img) && isa(dark_img, 'double'))
refimages = nan(size(refimages)); % fill with NaNs
absimages = nan(size(absimages));
refimages(:,:,k) = nan(size(refimages(:,:,k))); % fill with NaNs
absimages(:,:,k) = nan(size(absimages(:,:,k)));
else
refimages(:,:,k) = subtractBackgroundOffset(cropODImage(bkg_img, center, span), fraction)';
absimages(:,:,k) = subtractBackgroundOffset(cropODImage(calculateODImage(atm_img, bkg_img, dark_img, ImagingMode, PulseDuration), center, span), fraction)';

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@ -90,8 +90,8 @@ for k = 1 : length(files)
(isempty(bkg_img) && isa(bkg_img, 'double')) || ...
(isempty(dark_img) && isa(dark_img, 'double'))
refimages = nan(size(refimages)); % fill with NaNs
absimages = nan(size(absimages));
refimages(:,:,k) = nan(size(refimages(:,:,k))); % fill with NaNs
absimages(:,:,k) = nan(size(absimages(:,:,k)));
else
refimages(:,:,k) = subtractBackgroundOffset(cropODImage(bkg_img, center, span), fraction)';
absimages(:,:,k) = subtractBackgroundOffset(cropODImage(calculateODImage(atm_img, bkg_img, dark_img, ImagingMode, PulseDuration), center, span), fraction)';

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@ -1,4 +1,4 @@
%% ===== Settings =====
%% ===== D-S Settings =====
groupList = ["/images/MOT_3D_Camera/in_situ_absorption", "/images/ODT_1_Axis_Camera/in_situ_absorption", ...
"/images/ODT_2_Axis_Camera/in_situ_absorption", "/images/Horizontal_Axis_Camera/in_situ_absorption", ...
"/images/Vertical_Axis_Camera/in_situ_absorption"];
@ -45,28 +45,28 @@ zoom_size = 50; % Zoomed-in region around center
% Plotting and saving
scan_parameter = 'ps_rot_mag_fin_pol_angle';
% scan_parameter = 'rot_mag_field';
scan_parameter_text = 'Angle = ';
% scan_parameter_text = 'BField = ';
savefileName = 'DropletsToStripes';
font = 'Bahnschrift';
if strcmp(savefileName, 'DropletsToStripes')
scan_groups = 0:5:45;
scan_groups = 0:1:40;
titleString = 'Droplets to Stripes';
elseif strcmp(savefileName, 'StripesToDroplets')
scan_groups = 45:-5:0;
scan_groups = 40:-1:0;
titleString = 'Stripes to Droplets';
end
% Flags
skipUnshuffling = true;
skipNormalization = true;
skipUnshuffling = false;
skipPreprocessing = true;
skipMasking = true;
skipIntensityThresholding = true;
skipBinarization = true;
skipMovieRender = true;
skipSaveFigures = true;
skipSaveFigures = false;
skipSaveOD = true;
%% ===== Load and compute OD image, rotate and extract ROI for analysis =====
% Get a list of all files in the folder with the desired file name pattern.
@ -90,15 +90,15 @@ for k = 1 : length(files)
(isempty(bkg_img) && isa(bkg_img, 'double')) || ...
(isempty(dark_img) && isa(dark_img, 'double'))
refimages = nan(size(refimages)); % fill with NaNs
absimages = nan(size(absimages));
refimages(:,:,k) = nan(size(refimages(:,:,k))); % fill with NaNs
absimages(:,:,k) = nan(size(absimages(:,:,k)));
else
refimages(:,:,k) = subtractBackgroundOffset(cropODImage(bkg_img, center, span), fraction)';
absimages(:,:,k) = subtractBackgroundOffset(cropODImage(calculateODImage(atm_img, bkg_img, dark_img, ImagingMode, PulseDuration), center, span), fraction)';
end
end
%% ===== Fringe removal =====
% ===== Fringe removal =====
if removeFringes
optrefimages = removefringesInImage(absimages, refimages);
@ -183,18 +183,18 @@ for k = 1:N_shots
end
% Group by scan parameter values (e.g., alpha, angle, etc.)
[unique_scan_parameter_values, ~, idx] = unique(scan_parameter_values);
N_params = length(unique_scan_parameter_values);
[unique_scan_parameter_values, ~, idx] = unique(scan_parameter_values);
N_params = length(unique_scan_parameter_values);
% Define angular range and conversion
angle_range = 180;
angle_per_bin = angle_range / N_angular_bins;
max_peak_angle = 180;
max_peak_bin = round(max_peak_angle / angle_per_bin);
angle_range = 180;
angle_per_bin = angle_range / N_angular_bins;
max_peak_angle = 180;
max_peak_bin = round(max_peak_angle / angle_per_bin);
% Parameters for search
window_size = 10;
angle_threshold = 100;
window_size = 10;
angle_threshold = 100;
% Initialize containers for final results
mean_max_g2_values = zeros(1, N_params);
@ -293,7 +293,7 @@ for val = scan_groups
continue;
end
g2_vals = g2_all_per_group{i};
g2_vals = max_g2_all_per_group{i};
g2_vals = g2_vals(~isnan(g2_vals));
if isempty(g2_vals)
@ -336,7 +336,6 @@ for val = scan_groups
end
end
%% Plot all cumulants
figure(3)
set(gcf, 'Color', 'w', 'Position', [100 100 950 750])

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@ -0,0 +1,295 @@
%% Evolve to skewed to single gaussian with lower mean
clear; clc;
N_params = 50;
N_reps = 500;
alpha_values = linspace(0, 45, N_params);
all_data = cell(1, N_params);
% Transition control
alpha_start = 5; % where transition begins
alpha_end = 40; % where transition ends
mu_start = 1.2; % high initial mean
mu_end = 0.8; % low final mean
sigma_start = 0.2; % wide initial std
sigma_end = 0.07; % narrow final std
max_skew = 5; % peak skew strength
% Loop through alpha
for i = 1:N_params
alpha = alpha_values(i);
% Normalized transition variable t [0, 1]
t = min(max((alpha - alpha_start) / (alpha_end - alpha_start), 0), 1);
% Use cosine-based smooth interpolation
smooth_t = (1 - cos(pi * t)) / 2; % ease-in-out
% Mean and sigma interpolation (smoothly decrease)
mu = mu_start * (1 - smooth_t) + mu_end * smooth_t;
sigma = sigma_start * (1 - smooth_t) + sigma_end * smooth_t;
% Skewness: sinusoidal profile, max at middle
skew_strength = max_skew * sin(t * pi);
% Generate data
if abs(skew_strength) < 1e-2 % near-zero skew, use normal
data = normrnd(mu, sigma, [N_reps, 1]);
else
data = skewnormrnd(mu, sigma, skew_strength, N_reps);
end
all_data{i} = data;
% Cumulants
kappa = computeCumulants(data, 6);
mean_vals(i) = kappa(1);
var_vals(i) = kappa(2);
skew_vals(i) = kappa(3);
kurt_vals(i) = kappa(4);
kappa5_vals(i) = kappa(5);
kappa6_vals(i) = kappa(6);
end
%% Evolve to bimodal
clear; clc;
N_params = 50;
N_reps = 500;
alpha_values = linspace(0, 45, N_params);
all_data = cell(1, N_params);
bimodal_start = 20; % start earlier
transition_width = 5; % wider window for smoothness
for i = 1:N_params
alpha = alpha_values(i);
if alpha < (bimodal_start - transition_width)
% Pure skewed unimodal, smaller max skewness for subtlety
skew_strength = 3 * (alpha / bimodal_start);
data = skewnormrnd(1, 0.1, skew_strength, N_reps);
elseif alpha <= (bimodal_start + transition_width)
% Smooth transition window
t = (alpha - (bimodal_start - transition_width)) / (2 * transition_width);
% Weights transition 1 -> 0.7
w1 = 1 - 0.3 * t;
w2 = 1 - w1;
% Peak separation smaller (max delta = 0.3)
delta_max = 0.3;
delta = delta_max * t;
mu1 = 1 - delta;
mu2 = 1 + delta;
sigma1 = 0.1;
sigma2 = 0.1;
N1 = round(N_reps * w1);
N2 = N_reps - N1;
mode1_samples = normrnd(mu1, sigma1, [N1, 1]);
mode2_samples = normrnd(mu2, sigma2, [N2, 1]);
data = [mode1_samples; mode2_samples];
data = data(randperm(length(data)));
else
% After transition: bimodal, but not strongly balanced
w1 = 0.7;
w2 = 0.3;
mu1 = 1 - 0.3;
mu2 = 1 + 0.3;
sigma1 = 0.1;
sigma2 = 0.1;
N1 = round(N_reps * w1);
N2 = N_reps - N1;
mode1_samples = normrnd(mu1, sigma1, [N1, 1]);
mode2_samples = normrnd(mu2, sigma2, [N2, 1]);
data = [mode1_samples; mode2_samples];
data = data(randperm(length(data)));
end
all_data{i} = data;
kappa = computeCumulants(data,6);
mean_vals(i) = kappa(1);
var_vals(i) = kappa(2);
skew_vals(i) = kappa(3);
kurt_vals(i) = kappa(4);
kappa5_vals(i) = kappa(5);
kappa6_vals(i) = kappa(6);
end
%% Animate evolving distribution and cumulant value
figure(1); clf;
set(gcf, 'Color', 'w', 'Position',[100 100 1300 750])
for i = 1:N_params
clf;
% PDF
subplot(1,2,1); cla; hold on;
data = all_data{i};
% Plot histogram with normalized PDF
histogram(data, 'Normalization', 'pdf', 'BinWidth', 0.03, ...
'FaceColor', [0.3 0.5 0.8], 'EdgeColor', 'k', 'FaceAlpha', 0.6);
title(sprintf('Histogram at $\\alpha = %.1f^\\circ$', alpha_values(i)), ...
'Interpreter', 'latex', 'FontSize', 16);
xlabel('$\mathrm{max}[g^{(2)}]$', 'Interpreter', 'latex', 'FontSize', 14);
ylabel('PDF', 'FontSize', 14);
set(gca, 'FontSize', 12); grid on;
xlim([0.5, 1.8]);
% Cumulant evolution (e.g., Variance)
subplot(1,2,2); hold on;
plot(alpha_values(1:i), var_vals(1:i), 'bo-', 'LineWidth', 2);
title('Cumulant Tracking', 'Interpreter', 'latex', 'FontSize', 16);
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', 14);
ylabel('$\kappa_2$', 'Interpreter', 'latex', 'FontSize', 14);
xlim([0, 45]); grid on;
set(gca, 'FontSize', 12);
pause(0.3);
end
%% === Compute 2D PDF heatmap: f(x, alpha) ===
x_grid = linspace(0.5, 1.8, 200); % max[g²] values on y-axis
pdf_matrix = zeros(numel(x_grid), N_params); % Now: rows = y, columns = alpha
for i = 1:N_params
data = all_data{i};
f = ksdensity(data, x_grid, 'Bandwidth', 0.025);
pdf_matrix(:, i) = f; % Transpose for y-axis to be vertical
end
% === Plot PDF vs. alpha heatmap ===
figure(2); clf;
set(gcf, 'Color', 'w', 'Position',[100 100 950 750])
imagesc(alpha_values, x_grid, pdf_matrix);
set(gca, 'YDir', 'normal'); % Flip y-axis to normal orientation
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', 14);
ylabel('$\mathrm{max}[g^{(2)}]$', 'Interpreter', 'latex', 'FontSize', 14);
title('Evolving PDF of $\mathrm{max}[g^{(2)}]$', ...
'Interpreter', 'latex', 'FontSize', 16);
colormap(Colormaps.coolwarm()); % More aesthetic than default
colorbar;
c = colorbar;
ylabel(c, 'PDF', 'FontSize', 14, 'Interpreter', 'latex');
set(gca, 'FontSize', 14);
%% === Plotting ===
figure(1)
set(gcf, 'Color', 'w', 'Position', [100 100 950 750])
scan_vals = alpha_values; % your parameter sweep values
% Define font style for consistency
axis_fontsize = 14;
label_fontsize = 16;
title_fontsize = 16;
% 1. Mean with error bars (if you have error data, else just plot)
% If no error, replace errorbar with plot or omit error data
% For now, no error bars assumed
subplot(3,2,1);
plot(scan_vals, mean_vals, 'o-', 'LineWidth', 1.5, 'MarkerSize', 6);
title('Mean of Distribution', 'FontSize', title_fontsize, 'Interpreter', 'latex');
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', label_fontsize);
ylabel('$\kappa_1$', 'Interpreter', 'latex', 'FontSize', label_fontsize);
set(gca, 'FontSize', axis_fontsize);
grid on;
% 2. Variance
subplot(3,2,2);
plot(scan_vals, var_vals, 's-', 'LineWidth', 1.5, 'MarkerSize', 6);
title('Variance of Distribution', 'FontSize', title_fontsize, 'Interpreter', 'latex');
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', label_fontsize);
ylabel('$\kappa_2$', 'Interpreter', 'latex', 'FontSize', label_fontsize);
set(gca, 'FontSize', axis_fontsize);
grid on;
% 3. Skewness
subplot(3,2,3);
plot(scan_vals, skew_vals, 'd-', 'LineWidth', 1.5, 'MarkerSize', 6);
title('Skewness of Distribution', 'FontSize', title_fontsize, 'Interpreter', 'latex');
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', label_fontsize);
ylabel('$\kappa_3$', 'Interpreter', 'latex', 'FontSize', label_fontsize);
set(gca, 'FontSize', axis_fontsize);
grid on;
% 4. Kurtosis
subplot(3,2,4);
plot(scan_vals, kurt_vals, '^-', 'LineWidth', 1.5, 'MarkerSize', 6);
title('Kurtosis of Distribution', 'FontSize', title_fontsize, 'Interpreter', 'latex');
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', label_fontsize);
ylabel('$\kappa_4$', 'Interpreter', 'latex', 'FontSize', label_fontsize);
set(gca, 'FontSize', axis_fontsize);
grid on;
% 5. 5th-order cumulant
subplot(3,2,5);
plot(scan_vals, kappa5_vals, 'v-', 'LineWidth', 1.5, 'MarkerSize', 6);
title('Fifth-order Cumulant of Distribution', 'FontSize', title_fontsize, 'Interpreter', 'latex');
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', label_fontsize);
ylabel('$\kappa_5$', 'Interpreter', 'latex', 'FontSize', label_fontsize);
set(gca, 'FontSize', axis_fontsize);
grid on;
% 6. 6th-order cumulant
subplot(3,2,6);
plot(scan_vals, kappa6_vals, '>-', 'LineWidth', 1.5, 'MarkerSize', 6);
title('Sixth-order Cumulant of Distribution', 'FontSize', title_fontsize, 'Interpreter', 'latex');
xlabel('$\alpha$ (degrees)', 'Interpreter', 'latex', 'FontSize', label_fontsize);
ylabel('$\kappa_6$', 'Interpreter', 'latex', 'FontSize', label_fontsize);
set(gca, 'FontSize', axis_fontsize);
grid on;
% Super title (you can customize the string)
sgtitle('Cumulants of a simulated evolving distribution', ...
'FontWeight', 'bold', 'FontSize', 18, 'Interpreter', 'latex');
%% === Helper: Cumulant Calculation ===
function kappa = computeCumulants(data, max_order)
data = data(:);
mu = mean(data);
c = zeros(1, max_order);
centered = data - mu;
for n = 1:max_order
c(n) = mean(centered.^n);
end
kappa = zeros(1, max_order);
kappa(1) = mu;
kappa(2) = c(2);
kappa(3) = c(3);
kappa(4) = c(4) - 3*c(2)^2;
kappa(5) = c(5) - 10*c(3)*c(2);
kappa(6) = c(6) - 15*c(4)*c(2) - 10*c(3)^2 + 30*c(2)^3;
end
%% === Helper: Skewed Normal Distribution ===
function x = skewnormrnd(mu, sigma, alpha, n)
% Skew-normal using Azzalini's method
delta = alpha / sqrt(1 + alpha^2);
u0 = randn(n,1);
v = randn(n,1);
u1 = delta * u0 + sqrt(1 - delta^2) * v;
x = mu + sigma * u1 .* sign(u0);
end