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Paul Hoffrichter
on 10 Jul 2021

Dear Shimelis, I am assuming that you wish to discuss this problem further and need additional assistance. Since my time is extremely limited due to work and study obligations, I hope you will ask another question. As a community, we will all take a look and try to help you further.

Best Regards, Paul

Paul Hoffrichter
on 9 Jul 2021

Edited: Paul Hoffrichter
on 9 Jul 2021

Here is some made up data to illustrate one approach:

x = [ 0 1.1 2 3.3 5.12];

y = [146 145.9 145.8 139 128;

133 132.8 132 114 133;

119 118 116 102 133 ];

plot(x, y, '-bo')

Sean Brennan
on 9 Jul 2021

Like the previous answer said: be sure to plot x values AND y values. MATLAB allows you to plot data in the form:

data = rand(10,1); % Create 10 random points

plot(data); % Plot ONLY the y values - the x-values default to the indices of y

But this plots the data versus its index, in this case from 1 to 10. Yes, this is confusing because the plotting works, but the x-values are missing!

The plot command is normally used with x AND y values. For example, let's say the x-axis values associated with the data are from 0.1 to 1, incrementing by 0.1. Then we can plot the results as:

% Create a column of x data starting at 0.1 up to 1,

% incrementing by 0.1 (the ' symbol converts the row data to column)

xdata = (0.1:0.1:1)';

% Create the random y data column using the rand command

ydata = rand(10,1)

% Plot x versus y

plot(xdata,ydata);

You can modify the plot command, specify a figure, etc. Type "help plot" to learn more about this powerful and probably most often used MATLAB command.

dpb
on 9 Jul 2021

x=[0:size(Throughput,2)-1].'; % generate temporary x vector for convenience from 0

hL=plot(x,1E-6*Throughput(1:4,;).'); % plot first four rows of array as columns

salt to suit.

If there are only 4 rows in Throughput, then can dispense with the indexing expression entirely.

plot() will treat each column in the Y argument if an array as a separate variable; hence the transpose. Saves the explicit reference to have to plot each individually.

See the documentation for plot for all the syntax options; saving the line handles in hL lets you adjust line properties as desired.

Paul Hoffrichter
on 12 Jul 2021

First of all, you should be aware that the following two expressions are equivalent:

>> 1:5.12

ans =

1 2 3 4 5

>> 1:5

ans =

1 2 3 4 5

Are you just wanting to label the axis from 0:4 instead of 1:5? If so, then this works:

figure(2)

x = 0:4;

plot(x, Throughput./1e6);

legend('0.5 m/s','1 m/s','1.5 m/s','2 m/s');

xlabel('TTT_{W-L} index (0 sec to 5.12 sec)');

ylabel('Throughput)');

axis([0 5 -inf inf]);

hold off

grid on

box on

The left figure is from your original program. The right figure, is figure(2) from the code in this post.

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