Bug 427190

Summary: pinebook labplot2 inability to produce any fitting analysis and xy curve from a mathematical equation
Product: [Applications] LabPlot2 Reporter: Awangku Junaidi bin Pengiran Haji Samat@Pengiran Haji Sahbudin <junaidi756>
Component: generalAssignee: Stefan Gerlach <stefan.gerlach>
Status: RESOLVED FIXED    
Severity: major CC: misterx.mi66, neko.crys, stefan.gerlach
Priority: NOR    
Version: 2.8.0   
Target Milestone: ---   
Platform: Manjaro   
OS: Linux   
Latest Commit: https://invent.kde.org/education/labplot/commit/ddccdca36c6c598453b8a01fd76eb1d54bb1c933 Version Fixed In: 2.8.2
Sentry Crash Report:

Description Awangku Junaidi bin Pengiran Haji Samat@Pengiran Haji Sahbudin 2020-10-01 01:35:04 UTC 
SUMMARY
In pinebook manjaro, updated to the latest stable updates, the inability to produce any fitting analysis and plotting xy curve from a mathematical equation shows that they both should stem from the same problem. 

Although during fitting, the log says that it was successful, there's no such fitting drawn on the graph of said data. This problem was repeated successfully each time.

I've double check the dependencies on the file and double check with requirements on compiling labplot2, however did not try to compile it myself since i'm just a regular linux user and haven't dabbled with the deeper stuff.


STEPS TO REPRODUCE
1. run labplot2 in pinebook
2. input any data from any dataset collection
3. plot the graph successfully
4. attempt to fit data linearly, realize that although fitting logs says that it was successful, there's nothing added to the graph.
5. attempt to create xy plot from mathematical equation, the input box remains red and the recalculate button remains greyed out, therefore impossible to plot.

OBSERVED RESULT
no fitting line and no xy curve from mathematical equation successfully drawn on graph

EXPECTED RESULT
fitting line and xy curve from mathematical equation drawn on graph, alongside raw data

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
Comment 1 Stefan Gerlach 2020-10-03 19:51:24 UTC 
The reported problems may be explained by a parser problem on ARM platforms. I don't have access to any ARM system myself so anyone reproducing this on ARM would be welcome. Also comparing to Manjaro x86-64 would be great. Which Manjaro version do you have?
There will be some updates on the parser code in 2.8.1 so please try again when 2.8.1 is available.
Comment 2 Marcel 2020-11-12 16:22:51 UTC 
I can confirm this bug to be not exclusively limited to pinebooks or arm.
I have the same problem on an HP laptop with amd64 architecture and Debian unstable.

Labplot does not perform fits with custom equations, the field for the custom equation stays red and no fit appears on the worksheet. After trying to fit with a custom equation fitting with the predefined models like polynomial is also impossible.

I can also confirm the problem with plotting an xy-curve form a mathematical equation, the field for entering the equation stays red no matter what and no curve appears on the worksheet.


SOFTWARE / OS VERSIONS:
Labplot Version: 2.8.1
Operating System: Debian GNU/Linux
KDE Plasma Version: 5.19.5
KDE Frameworks Version: 5.74.0
Qt Version: 5.15.1
Kernel Version: 5.9.7-towo.1-siduction-amd64
OS Type: 64-bit
Comment 3 Stefan Gerlach 2020-11-12 21:52:43 UTC 
I was able to reproduce the problem on Debian testing now. I will take a closer look.
Comment 4 Stefan Gerlach 2020-11-15 12:01:19 UTC 
Git commit 71afe611a132415791dd28a64e1a35d5804cda15 by Stefan Gerlach.
Committed on 15/11/2020 at 12:00.
Pushed by sgerlach into branch 'master'.

parser: explicitly reset error count in parser
FIXED-IN: 2.8.2

M  +1    -0    src/backend/gsl/parser.y

https://invent.kde.org/education/labplot/commit/71afe611a132415791dd28a64e1a35d5804cda15
Comment 5 Stefan Gerlach 2020-11-15 12:19:44 UTC 
Git commit ddccdca36c6c598453b8a01fd76eb1d54bb1c933 by Stefan Gerlach.
Committed on 15/11/2020 at 12:19.
Pushed by sgerlach into branch 'release/2.8'.

parser: explicitly reset error count in parser
FIXED-IN: 2.8.2

M  +1    -0    src/backend/gsl/parser.y

https://invent.kde.org/education/labplot/commit/ddccdca36c6c598453b8a01fd76eb1d54bb1c933
Comment 6 Stefan Gerlach 2020-12-15 13:24:40 UTC 
*** Bug 430417 has been marked as a duplicate of this bug. ***