How can I plot (scatter diagram) three data series at the same time?

Good day all,

I have following dataset. Now I would like to plot the data using scatter. X axis is temperature and Y axis is molality. The data set includes a wide range of different pressures (0 to 20.000 bar) and I would like to create plots (scatter) in which you can find the temperature-molality diagrams depending with the same pressure value. So e.g. diagram 1 includes all temperature-molality relation with 500 bar, diagram 2 includes all l temperature-molality relation with 1000 bar and so on.

Many thanks for your support.

[Hans Lipton]

I am very new to Matlab, so I would be very happy if you could add a code, too. Many thanks!

Answer 1

[Johan]

Hello Robert,

You can use conditional statement inside an array call to filter it with your wanted data:

myarray = [500,1,2;500,2,3;500,4,2;1000,4,5;1000,6,7]

myarray = 5×3

500 1 2 500 2 3 500 4 2 1000 4 5 1000 6 7

%filter for 500 in first column
%the conditional statement abs(myarray(:,1)-condition)<eps looks for values of
%myarray that are less than 1 epsilon away from condition
condition = 500;
myarray(abs(myarray(:,1)-condition)<eps,:) 

ans = 3×3

500 1 2 500 2 3 500 4 2

%plot conditional data
figure(1)
plot(myarray(abs(myarray(:,1)-condition)<eps,2), myarray(abs(myarray(:,1)-condition)<eps,3),'x-')

figure(2)
condition = 1000;
plot(myarray(abs(myarray(:,1)-condition)<eps,2), myarray(abs(myarray(:,1)-condition)<eps,3),'x-')

Hope this helps.

[Hans Lipton]

I am very happy about your support, this helps a lot. Many thanks, Johan!