Clear Filters
Clear Filters

how to find area under curve for every 10msec?

1 view (last 30 days)
Hi, i have tried finding area under curve for each parabolic curve or for every 10msec time (as shown in the figure) but i coudn't find it.I only can find the whole area under curve of the graph by using the code as i attached. How to find area under curve for every 10msec time and plot them as a graph.Hope someone can help me with this.Thank you in advance.
T1=readtable ('t.txt');
t = T1.('TIME'); v = T1.('TORQUE');
plot(t,v)
grid
xlabel('t')
ylabel('v')
title('TORQUE VS TIME')
hold on;
Area=trapz(t,v);
plot(Area)
openfig('torque vs time.fig');

Accepted Answer

Scott MacKenzie
Scott MacKenzie on 13 Aug 2021
Edited: Scott MacKenzie on 15 Aug 2021
Here's solution that shows the slope (derivative) and area (integral) sample-to-sample in the signal. The sample period is 10 ms. For illustration, there are plots for the entire signal and for just the first 300 samples of the signal.
f = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/708907/t.txt';
M = readmatrix(f);
time = M(:,3);
torque = M(:,4);
Ps = mean(diff(time)); % sample period
% slope, sample to sample
s = diff(torque) / Ps; % slope = dy/dz
s = [0 s'];
tiledlayout(3,2);
% all samples
nexttile(1);
plot(time, torque); % signal
title('All samples');
nexttile(3);
plot(time, s); % slope (sample to sample)
title('diff (slope)');
nexttile(5);
tqa1 = (torque(1:end-1) + torque(2:end)) / 2 * Ps; % area under (sample to sample)
tqa1 = [0; tqa1];
plot(time, tqa1);
title('area under (10-ms intervals)');
% 1st 300 samples
m = 300;
nexttile(2);
plot(time(1:m),torque(1:m)); % signal
title('First 300 samples');
nexttile(4);
plot(time(1:m),s(1:m)); % slope (sample to sample)
title('diff (slope)');
nexttile(6);
tqa2 = (torque(1:m-1) + torque(2:m)) / 2 * Ps; % area under (sample to sample)
tqa2 = [0; tqa2];
plot(time(1:m),tqa2);
title('area under (10-ms intervals)');

More Answers (0)

Categories

Find more on Statistics and Machine Learning Toolbox in Help Center and File Exchange

Products

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!