Dear Roman, If I understand correctly, your question is more about the fact that you find an oval instead of a circle. Is that right?
In that case, the answer is: pgfplots uses the loglog coordinate system as expected, but it rescales the unit vectors in order to a) fit the axis into the prescribed dimensions and b) to view a "good" portion of the axis. This rescaling is usually not the same for both axis, resulting in an oval rather than a circle. Consider using the "axis equal" option in order to get a real circle (although this will change your limits such that the axis still fits into the dimensions). Does this help? Concerning the placement: it seems to me that the placement is correct. The unit "0.25" and the coordinate "(0,-0.25)" are expressed in the completely scaled pgfplots system which means that their meaning is a little bit unclear. Best regards Christian Am 11.04.2011 22:13, schrieb Roman Yurchak: > Hello, > > I would like to make annotations to a loglog figure using 'after end > axis' as explained in the manual. The minimal working example would be: > > %-------------------------------------------------------------------- > \begin{tikzpicture} > \begin{axis}[ > xmin=5.0e-01, xmax=1.0e+01, > ymin=3.0e-01, ymax=2.5e+01, > xmode=log, > ymode=log, > after end axis/.code={ > \begin{scope}[shift={(axis cs:1.,10.)}] > \draw[thin, gray] (0,0) circle (0.25); > \draw[<->] (0,-0.25) -- (0,0.25); > \draw[<->, blue] (-0.25,0) -- (0.25,0); > \end{scope} > }] > > %...data... > > \end{axis} > \draw[thin, red, shift={(2.5,4.5)}] (0,0) circle (0.25); > \end{tikzpicture} > %------------------------------------------------------------------- > > however it seems that the the coordinate system I get inside "after > end axis/.code" is not the the normal one (nor the loglog) but something > linear with xscale!=yscale: it draws an oval instead of a circle. > I'm not very familiar with tikz coordinate system, so am I doing > something wrong here? > > Thank you in advance, ------------------------------------------------------------------------------ Benefiting from Server Virtualization: Beyond Initial Workload Consolidation -- Increasing the use of server virtualization is a top priority.Virtualization can reduce costs, simplify management, and improve application availability and disaster protection. Learn more about boosting the value of server virtualization. http://p.sf.net/sfu/vmware-sfdev2dev _______________________________________________ Pgfplots-features mailing list Pgfplots-features@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/pgfplots-features