Re: [matplotlib-devel] quiver API

Looks good, but I think it also needs a 'width' or 'weight' kwarg.
I was also thinking of putting at least a couple of different arrow 
styles in via an 'arrowstyle' kwarg, so I'd pass those through to the 
Arrow LineCollection.

Gary R.

Rob Hetland wrote:
> It might make some sense to rethink the quiver API, especially since it 
> seems there are a few people working toward the same goal (I will help, 
> too, if someone can give me some tasks..).
> 
> Here's a strawman quiver API:
> 
> quiver(x, y, u, v, color='b', scale=1.0, scale_to_grid=False, **kwargs)
> 
>   x, y - quiver should be able to handle *random* (x, y) points (right 
> now, it seems to expect meshed positions -- it seems this is 
> an unnecessary constraint.)
> 
>   color - could be a plot-style color (e.g., 'b', 'k', 'm'), a tuple, or 
> an array the same size as x and y to be mapped using the colormap.
> 
>   scale - is a multiplier for the vector length.
> 
>   scale_to_grid - is a boolean that specifies whether the vectors should 
> be in grid coordinates (True), or scaled to fit nicely (False -- vectors 
> are scaled to fit nice, then multiplied by scale).
> 
>   Plus all the normal kwargs (e.g., cmap). 
> 
> 
> Other potential things to consider include scaling the aspect of the 
> vectors so that the grid can have an aspect ratio unequal to one, but 
> the vectors still scale correctly (i.e., u and v have the same length, 
> even when x is twice y).  
> 
> Finally, I have always wanted an easy way to do curly vectors -- similar 
> to streaklines --  but this might be beyond the scope of the simple 
> quiver command.
> 
> -Rob