[EMAIL PROTECTED] wrote: > Recently I noticed that the quiver plots all make the arrows as if the > plot had aspect ratio 1. See, for example, the documentation for quiver: > > In all cases the arrow aspect ratio is 1, so that if *U*==*V* the > angle of the arrow on the plot is 45 degrees CCW from the *x*-axis. > > > This seems to make the plot pretty useless if the aspect ratio is not 1, > since then the slopes of the arrows do not match up with the coordinate > axes. What is the reason for this design decision? Does it have to do > with the arrows distorting if the aspect ratio is not 1? At one time,
No, the design suits my applications: I want to plot arrows indicating ocean current vectors as a function of position in the horizontal, or as a function of depth and time. But I don't think the design is limiting. See below. > there was talk of adding a line version of quiver (as opposed to the > patch version there now). See > http://article.gmane.org/gmane.comp.python.matplotlib.devel/1885. Has > that happened? I suppose a line version would allow different aspect > ratios. No, in this respect it would be no different. And no, a line version has not been added. > > Is there an easy way to get a correct quiver plot (i.e., correct slopes) > now if the aspect ratio is not 1? Please provide a script that illustrates what you think is the problem. Exactly what is it that you want to do, and don't know how to do with quiver as it is? Note that you have full control over U and V; you can make the arrows point any direction you want, and be any length you want. And you can locate them anywhere you want. Basemap illustrates how quiver can be used with curvilinear coordinates; the U and V are adjusted to align the arrows with the coordinates. It is possible that quiver needs more modification to work properly and flexibly with the new transforms implementation; in fact I know of a bug that this introduced, and I will commit a correction shortly. I have not looked into quiver behavior with transforms-based projections. They might indeed call for a design change. Eric ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
