MantisBT - ParaView
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0015652ParaView(No Category)public2015-08-13 18:352016-01-08 15:32
Ken Moreland 
Utkarsh Ayachit 
normalminorhave not tried
closedfixed 
git-master 
5.05.0 
Sandia
incorrect functionality
0015652: Quartile chart is wrong
When you plot a large selection over time with the selection statistics on, you get a quartile chart that is clearly wrong. To replicate, do the following:

1. Open can.ex2. Load all variables. Apply.
2. Use a select cell through to select everything.
3. Open the Find Data dialog.
4. Click Freeze Selection.
5. Click Plot Selection Over Time.
6. Turn on "Only Report Selection Statistics". Apply.

In the resulting quartile chart you can see that the average line in the lower left is drawn in the upper quartile, which is clearly wrong. (See the attached image.) Either the plot selection over time filter is computing bad statistics or the quartile chart is plotting it wrong.
No tags attached.
png Screen Shot 2015-08-13 at 4.34.39 PM.png (208,592) 2015-08-13 18:35
https://www.vtk.org/Bug/file/9871/Screen%20Shot%202015-08-13%20at%204.34.39%20PM.png
png
Issue History
2015-08-13 18:35Ken MorelandNew Issue
2015-08-13 18:35Ken MorelandFile Added: Screen Shot 2015-08-13 at 4.34.39 PM.png
2015-08-17 16:16Alan ScottProjectTBD => Sandia
2015-08-17 16:16Alan ScottNote Added: 0035009
2015-08-17 16:16Alan ScottTarget Version => 4.5
2015-08-18 11:59Ken MorelandNote Added: 0035017
2015-09-11 16:44Utkarsh AyachitTarget Version4.5 => 5.1
2015-11-09 13:32Utkarsh AyachitNote Added: 0035438
2015-11-09 14:01Utkarsh AyachitNote Added: 0035439
2015-11-09 14:01Utkarsh AyachitStatusbacklog => gatekeeper review
2015-11-09 14:01Utkarsh AyachitFixed in Version => git-master
2015-11-09 14:01Utkarsh AyachitResolutionopen => fixed
2015-11-09 14:01Utkarsh AyachitAssigned To => Utkarsh Ayachit
2015-11-17 14:23Utkarsh AyachitStatusgatekeeper review => customer review
2015-11-17 14:24Utkarsh AyachitNote Added: 0035456
2015-11-17 14:24Utkarsh AyachitNote Edited: 0035456bug_revision_view_page.php?bugnote_id=35456#r1399
2015-12-16 17:14Alan ScottNote Added: 0035583
2015-12-16 17:14Alan ScottStatuscustomer review => closed
2016-01-08 15:31Utkarsh AyachitTarget Version5.1 => 5.0
2016-01-08 15:32Utkarsh AyachitFixed in Versiongit-master => 5.0

Notes
(0035009)
Alan Scott   
2015-08-17 16:16   
Ken, Think it is OK to fix this next release (not this release)?
(0035017)
Ken Moreland   
2015-08-18 11:59   
Alan, that depends on the root cause of the problem. If ParaView is giving us bad values then it should be fixed the next release, but if this is just an odd interaction then I'm fine with pushing it back.

After giving this some thought, I suspect it is probably the latter. I think what is happening is that the quartiles are based on the distribution of the data. The median value by definition should always be between the two middle quartiles. However, the thick line is the average, not the median, which is slightly different. I suspect that in early timesteps you have a small set of values that are very large, which is bringing the average noticeably above zero even though more than 50% of the value are still zero (thus the median is zero).

Assuming this is the case, I am fine with pushing the fix off.

I'm not sure what the right answer is here. I don't think replacing the average with median is a good answer. Maybe we could have a second thinner and more subtle line showing the median. That should be easy to implement.
(0035438)
Utkarsh Ayachit   
2015-11-09 13:32   
Ken, your analysis is correct. The average needn't lie between the two middle quartiles. I can add a median line and also add checkboxes on the panel allow using to toggle visibility of both of these lines.
(0035439)
Utkarsh Ayachit   
2015-11-09 14:01   
Merge request:

https://gitlab.kitware.com/paraview/paraview/merge_requests/471 [^]
(0035456)
Utkarsh Ayachit   
2015-11-17 14:24   
Added ability to show median line as well as average line.

(0035583)
Alan Scott   
2015-12-16 17:14   
Spectacular.

Tested remote server, Linux, 5.0.0-RC2.