Problem in Visualising line plots and color coding the lines

I have 100 sets of probability data which ranges from 1E-4 to 1E-6 that I would like to plot as line graphs. To enhance the visualization, I plan to take the logarithm of the probabilities and color code by the log of probability that it would occur. Additionally, I aim to sort the lines so that the highest probabilities are plotted on top for better visibility. However, the current MATLAB code I have attempted is not yielding the desired outcome. I kindly request your assistance in identifying any errors and providing guidance on visualizing the data more effectively.

% Set the range of random numbers

minValue = 1E-6;

maxValue = 1E-4;

% Generate 100 random numbers

total_probability = minValue + (maxValue - minValue) * rand(1, 100);

% Take the logarithm of the probabilities

log_probabilities = log(total_probability);

% Sort the probabilities in descending order

[sorted_probabilities, sorted_indices] = sort(log_probabilities, 'descend');

% Sort the original data accordingly

sorted_data = total_probability(sorted_indices);

% Plot the line plots with color coding based on log probabilities

figure;

hold on;

for i = 1:length(sorted_data)

color_value = sorted_probabilities(i) / max(sorted_probabilities);

plot(sorted_data(i), 'Color', [color_value 0 0]);

end

hold off;

Answer 1

[ProblemSolver]

Hello @Mark:

You are on the right track however you do these minor changes:

Instead of this:

% Set the range of random numbers
minValue = 1E-6;
maxValue = 1E-4;

% Generate 100 random numbers
total_probability = minValue + (maxValue - minValue) * rand(1, 100);

% Take the logarithm of the probabilities
log_probabilities = log(total_probability);

Use this:

% Take the logarithm of the probabilities
log_probabilities = log10(total_probability);

Instead of this:

% Plot the line plots with color coding based on log probabilities
figure;
hold on;
for i = 1:length(sorted_data)
    color_value = sorted_probabilities(i) / max(sorted_probabilities);
    plot(sorted_data(i), 'Color', [color_value 0 0]);
end
hold off;

Use this:

% Create a color map for the plot
cmap = jet(length(sorted_data));

% Plot the line plots with color coding based on log probabilities
figure;
hold on;
for i = 1:length(sorted_data)
    plot([1, 2], [sorted_data(i), sorted_data(i)], 'Color', cmap(i, :));
end
hold off;

% Customize the plot
title('Line Plots of Logarithm of Probabilities');
xlabel('X');
ylabel('Probability');
colormap(cmap);
colorbar('Ticks', linspace(0, 1, length(sorted_data)), 'TickLabels', num2str(sorted_probabilities', '%0.2f'));

I hope this helps!

[Mark]

Thanks @ProblemSolver. It still doesn't show any line plots.

% Set the range of random numbers

minValue = 1E-6;

maxValue = 1E-4;

% Generate 100 random numbers

total_probability = minValue + (maxValue - minValue) * rand(1, 100);

% Take the logarithm of the probabilities

log_probabilities = log10(total_probability);

% Sort the probabilities in descending order

[sorted_probabilities, sorted_indices] = sort(log_probabilities, 'descend');

% Sort the original data accordingly

sorted_data = total_probability(sorted_indices);

% Plot the line plots with color coding based on log probabilities

figure;

hold on;

for i = 1:length(sorted_data)

color_value = (sorted_probabilities(i) - min(log_probabilities)) / (max(log_probabilities) - min(log_probabilities));

plot(sorted_data(i), 'Color', [color_value 0 0]);

end

hold off;

% Customize the plot

title('Line Plots of Logarithm of Probabilities');

xlabel('Index');

ylabel('Probability (log scale)');

colorbar;

colormap('jet');

[ProblemSolver]

Hello @Mark: Yeah I realized that it was missing something. I updated the code above, as well as I am providing the whole code here as well:

% Set the range of random numbers
minValue = 1E-6;
maxValue = 1E-4;

% Generate 100 random numbers
total_probability = minValue + (maxValue - minValue) * rand(1, 100);

% Take the logarithm of the probabilities
log_probabilities = log10(total_probability);

% Sort the probabilities in descending order
[sorted_probabilities, sorted_indices] = sort(log_probabilities, 'descend');

% Sort the original data accordingly
sorted_data = total_probability(sorted_indices);

% Create a color map for the plot
cmap = jet(length(sorted_data));

% Plot the line plots with color coding based on log probabilities
figure;
hold on;
for i = 1:length(sorted_data)
    plot([1, 2], [sorted_data(i), sorted_data(i)], 'Color', cmap(i, :));
end
hold off;

% Customize the plot
title('Line Plots of Logarithm of Probabilities');
xlabel('X');
ylabel('Probability');
colormap(cmap);
colorbar('Ticks', linspace(0, 1, length(sorted_data)), 'TickLabels', num2str(sorted_probabilities', '%0.2f'));