Unlocking the Power of Data Visualization with PyQtGraph
In the realm of data science and software development, effective visualization tools are critical for interpreting complex datasets. PyQtGraph emerges as a powerful library, offering advanced capabili...
https://news.lavx.hu/article/unlocking-the-power-of-data-visualization-with-pyqtgraph
@mcc I maintain #PyQtGraph ; and I can’t tell you how many issues I identify if I try and pretend like I am a complete newcomer, don’t look at past examples but look at the docs and try and plow forward.
Next minor task since I'm waiting on feedback for #PyQtGraph changes I'm trying to make; try and implement Custom sections in numpydoc (see: https://github.com/numpy/numpydoc/issues/202 ).
I should note, I have no idea how sphinx extensions work, but this feature would be very useful to #PyQtGraph and judging by the number of linked issues, quite a few other libraries.
Do you use #PyQtGraph with conda versions of #PySide bindings? Then this issue is very relevant to you. Please upvote:
https://bugreports.qt.io/plugins/servlet/mobile#issue/PYSIDE-3031
We have recently merged into the repo a new on of #OpenGL related improvements, mostly for 3D, but PColorMeshItem got some love too. If you use #PyQtGraph for 3D visualization, we’d love to hear back from you.
Every time I update the sphinx theme for #PyQtGraph I get a different CSS coloring issue.
For the record, I'm throwing no shade at the theme maintainers, it's not their fault that I'm probably modifying the underlying CSS in a way that is so bizarre that nobody that has any resemblance of knowing what they're doing would do 
Prompt: Black on black.
(I deliberately skipped Prompt 3, "Exactly 42 lines of code." which seemed both too constricting and not constricting enough.)
Layers upon layers upon layers.
I still like the basic idea here, but I couldn't make it work on multiple levels (how ironic).
I spent several hours trying to understand how color compositing works in general and in #qt in particular. I kind of got something fragile sort-of working.
When I gave up on Making It Perfect, I realized that looping a blizzard is unlikely to work.
Welp. This is a #learning #python #pyqtgraph project anyway and that goal was accomplished.
@davidr FYI #PyQtGraph has an issue with thick lines (>1px) and partial alpha. If the QPen instance has partial alpha, we can't use our fast "drawLines" codepath, and are stuck with "drawPath”, which performs _terribly_ with >1px lines. If you're plotting static plots, you may not notice, but if you're doing anything that updates frequently, you're likely to have problems.
So. I want to #pyqtgraph plot some colored items with medium alphas and then overlap them to produce the usual kindergarten color wheel results.
But it turns out that #pyqt only supports compositing in the RGB #color space.
In fact, the Wikipedia article makes it sound like alpha blending is only even *defined* for RGB. Which I guess makes sense for speed reasons, but I'd still expect some way to put in a callback or whatever for a custom mode.
I guess what I'll do it do all the HSV and compositing work in a #python #numpy array and the convert to an RGB image and display it that way...?
Unless there's a better idea?
It's February 1 and you know what that means!
#GENUARY!!
This is my first ever entry. Prompt is "Vertical or horizontal lines only."
ooooookaaaayyyyy!!!
Got the ticks #python #code working for "numbers" and "angles" (where the difference is what constitutes a "nice" value)
Just now made a #pyqtgraph with 4 subplots. Two default axes, two custom axes using "my" #algorithm for tick generation, one for "numbers" and one for "angles".
Very, very reasonable behavior! (bottom row is custom ticks) (I know radians are still technically angles, but that's not the point)(I just realized I should have called that feature "degrees" not "angles")
One potential upgrade is to compute something for minor ticks. How do I....oh, those are probably the next lower mantissa! Except for snow removal I have nothing else to do today, so....
@villares if you’re wanting live plot updates that’s sort of #PyQtGraph ‘s thing. I will freely admit that pyqtgraph does not have the plotting customization that matplotlib does but it’s very straight forward to integrate into a Qt application.
W H E W i finally did it
- created my own polar graph in #pyqtgraph
- created a subclass that maps azimuth to theta (easy) and elevation to R (not hard, but not necessarily obvious for stereographic projection)
- used that to re-implement the faulty graph I made like....6 years ago? also had to find and rewrite a bunch of code to use a great-circle distance from a point rather than azimuth/elevation ranges #python #space #math
The original toot in this chain is from 1/3, so that's exactly two weeks of A B S O L U T E P A N I C on my part
I mean, it was my bug. And it's kind of a dumb bug. And it has been keeping me from my regular #coding and also from doing a good job as a #mentor for the super-fresh new-hire
But it's really #adhd #rsd perfectionism/terror that drove me for these two weeks. I could barely think straight. I should probably note this at my adhd evaluation on 1/30.
I write #software at the intersection of #space, #signalprocessing and #radar. I've learned a LOT, but the radar is the fuzziest bc it's the hardest to hands-on learn on your own
Just found this great series about a #diy #sdr radar
https://www.youtube.com/watch?v=igrN_wd_g74&list=PLxC4LYGYcMqmPDEr8E8AlktQPcuHx4izm&pp=iAQB
(I'm doing the $200 level, not the $3k)
Extra cool sidenote, it's coded in #python and uses #pyqtgraph for exactly the reason I've switched from #matplotlib--it's 1000x faster and more versatile
When you have a holiday and decide to merge ~13 PRs in #PyQtGraph
My apologies to the contributors that waited quite some time for feedback or the PR to be merged.
I bought a heart rate monitor strap for on the treadmill and...oops, I got a new #adhd #hyoerfixation...on #medical #datascience
The app shows a "#poincare plot". That is a cardiac-specific term for a more general #math concept for investigating cyclical data. Maybe good for some of the #satellite #orbit stuff I've been doing!
Meanwhile, the actual use here is for "heart rate variability" which is the latest mostly-woo #health fad
But a great excuse to learn #ble and practice #pyqtgraph
I like to re-toot this link every time I use the palette again
@nedbat was mostly joking as the changelog for #PyQtGraph is a list of PRs, but in categories highlights, bug fixes, performance improvements, api changes, etc etc ... I know it's not great , but I've found that to be the fastest way to put something resembling something coherent.
One thing that I do hate about working in open source (while parenting and working a full time job) is that I know what I need to do to make something as good as the users deserve, I just don't have the time to do so.
@ocefpaf @hobu @sgillies @edsu In our respective fields, we can definitely depend on performance improvements from compiled extensions, in the case of numpy, more SIMD optimizations and the likes, but pure python performance improvements have been very in demand. Curious if any of the Qt bindings will support the noGIL version, and if so what that would mean for #PyQtGraph.
