MATLAB Answers

Plots - Two Y-Axis with Different Units

65 views (last 30 days)
Tony Rothschild
Tony Rothschild on 4 Dec 2019
Commented: Tony Rothschild on 4 Dec 2019
I need to plot a lot of data from an Excel file. I would like to plot one column of data (flow rate) against the left y-axis and have two columns of data (pressure drops) against the right y-axis. How do I do this?
I thought I could work it out using the help pages, but I have no idea how to code the data. I am importing it from Excel and plotting instead. At the moment the plot looks ridiculous because it is plotting it all against the left y-axis and the values for the pressure drops are small compared to the flow rate.


Sign in to comment.

Answers (1)

Raj on 4 Dec 2019
Since you have not shared the data, it is not possible to give exact solution to your problem but if you are looking for plotting on both primary (left side) and secondary axis (right side) of a graph, you should use yyaxis command.
See details here:
Hope this helps!

  1 Comment

Tony Rothschild
Tony Rothschild on 4 Dec 2019
I have attached a sample of the data. It is the final three columns that I would like to plot. Not all the values, but a selection of them where it shows a steady state. One is flow rate in litres per minute and the other two are pressure drops in bar.
The link provided was the one I used when I looked for a solution. Although I understand how to code that first plot, I don't know how to input the data from the Excel sheet. That's the reason I thought importing it would be easier. I basically want that but with the data I have. Then I can tweak a little with the editing tool.

Sign in to comment.

Sign in to answer this question.