# How can I plot the integration result?

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Commented: Star Strider on 21 Jun 2021
I used loop to do an integration to get velocity and position, but when I want to plot them, it showed error:
Error using plot
Vectors must be the same length.
Error in Droptest (line 30)
plot(time, V, 'm--')
Here is script I used:
%% Deformation Velocity
for i = 1:length(time)-1;
j = 1:length(xaccel)-1;
V0 = 0;
V = V0 + (xaccel(j+1)+xaccel(j)/2)*(time(i+1)-time(i));
end
I can't figure it out how to make them the same length and using the iterative at the same time.

Star Strider on 21 Jun 2021
If you want to plot the cumulative acceleration to get velocity and position, use the cumtrapz function:
t = linspace(0, 10); % Create Data
xaccel = exp(-0.25*t) .* sin(2*pi*t/10); % Create Data
xveloc = cumtrapz(t, xaccel); % Integrate
xposit = cumtrapz(t, xveloc); % Integrate
figure
plot(t, xaccel)
hold on
plot(t, xveloc)
plot(t, xposit)
hold off
grid
legend({'Acceleration','Velocity','Position'}, 'Location','best') .
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Star Strider on 21 Jun 2021
As always, my pleasure!