lineplot: SWT is not responding


Im running Ubuntu 22.04.1 LTS.

Often when I select data and hit “Show Lineplot” I have to wait very long and get the following:

SWT is not responding


before the “Line Plot Options” appear.

And sometimes I wait and wait and wait; and nothing happens.
What’s going on here?

It is like this when selecting the deb package hdfview ( ), so I built a shiny new hdfview (version 3.2.0) from source with openjdk-18-jdk; but it has the same behaviour.


Could it be the amount of data?


Hi, @albert.neu!

Can you give us a link to the data file?

If not, you can try the following 3 easy-to-use tools and
report us if they show the same behavior.

  1. Panoply
  2. ViTables
  3. HDFCompass

The 3rd option should be tried last since it’s old.

Finally, try the older version and see if it works for you:



unfortunately I cannot yet upload to this forum.
The file where lineplot is taking ages in HDFView (under Ubuntu Linux) can be downloaded here:
(to download hit the blue rectangle - file has 145.25 KB - download link only valid for one month)

The downloaded file is:

sha256sum: 7fc4363ac31449f77a7559aea242a06d17b37e5c228ed4c9750ad5d47a7d80ee

Decompress on linux with command:

xz -dk x.h5.xz

results in x.h5

Then open up in HDFView and go to mydata and try showing all the 28157 values in a lineplot.
(Please try it on Ubuntu: apt install hdfview
I’m using Ubuntu 22.04.1 Jammy LTS)

The cpu on one core goes permanantly to 100% … basically for ever. haha!

Can you reproduce that?

PS: If I use panoply, I can immediately get a lineplot displayed. No troubles with panoply!


I’m glad to hear that Panoply worked!

Thank you for providing sha256sum as well. :clap:

I tested the file using my Mac and 3.1.4.
It worked fine although HDFView’s color scheme is impossible to read any text. :disappointed_relieved:

Thus, I think the problem is in HDFView 3.2.0 + Ubuntu + jdk.
Please submit an issue

@byrn, is there an easy way to (unit-)test it automatically using GitHub Action?
It would be ideal if a few lines of HDF-Java test code can generate a PNG from line plot.