Eric Firing wrote:
Christopher Barker wrote:
Has anyone used MPL to make stick plots? If so, can I borrow your code?
If no one volunteers anything, then I suggest using quiver(..., headlength=0, headwidth=0, headaxislength=0), together with quiverkey(...). This will effectively give you a stick plot, with lots of flexibility.
Thanks, I was thinking that quiver() would get direction wrong, as the x and y scales are in totally different units, but it looks like that's not the case if you use the "angles" keyword:
angles: [‘uv’ | ‘xy’ | array]
With the default ‘uv’, 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. With ‘xy’, the arrow points from (x,y) to (x+u, y+v). Alternatively, arbitrary angles may be specified as an array of values in degrees, CCW from the x-axis.
> It could be implemented more efficiently in any of
several ways, but it would take work to do it well.
I hope I'll get time to do that, but I don't really like quiver stick plots anyway. I prefer plots (that I don't know the name of) that:
Time is on the x axis
Magnitude of the velocity is the x axis
At each data point, there is a dot, and the direction is given with a unit-length arrow originating at that dot, in the direction of the observation.
I wrote a version of this a while back with the old MPL transforms mechanism, but haven't taken the time to translate it.
Christopher Barker, Ph.D.
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