Bug 225178

Summary:	Transforming log-scaled axes is not intuitive
Product:	[Applications] kst	Reporter:	Michael Vincent <bug.zilla.vynce>
Component:	general	Assignee:	kst
Status:	RESOLVED FIXED
Severity:	normal	CC:	arwalker
Priority:	NOR
Version:	1.8.0
Target Milestone:	---
Platform:	unspecified
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Michael Vincent 2010-02-01 19:14:20 UTC

Version:           1.8.0 (using 3.5.10-3.fc10 Fedora, Fedora release 10 (Cambridge))
Compiler:          Target: i386-redhat-linux
OS:                Linux (i686) release 2.6.27.19-170.2.35.fc10.i686.PAE

1. Setup a plot. The vectors should have values in the 1000's.
2. Set the y axis to log scale.
3. Enable the right-axis transform and set the expression to y/1000.
4. The transform expression is applied to exponent of the left axis instead of the actual value.

For example:
I have a label on the left axis that says 10^5. If I set the transform expression to y/1000, I expect the corresponding label on the right axis to be 100. Instead it is 0.005. If I change the transform expression to 10^(y-3), it works correctly. The problem is that if you then disable log scaling, the transformation is wrong again and needs to be set back to y/1000. I don't think that toggling log scaling on and off should affect the transformed axis.

Comment 1 Andrew Walker 2010-02-01 22:55:30 UTC

SVN commit 1083771 by arwalker:

BUG:225178 Apply transformation of an axis to the original axes values, rather than their log values

 M  +26 -7     kst2dplot.cpp  


WebSVN link: http://websvn.kde.org/?view=rev&revision=1083771

Comment 2 Michael Vincent 2010-02-02 00:26:08 UTC

Thanks! It now works like I expected.

Comment 3 Andrew Walker 2010-03-30 01:26:41 UTC

Should have been marked as fixed with the commit, but apparently not!