Request for quiver plot

[abahm]

One feature is that is missing from the Julia plotting eco-system (Winston, Gadly, Plotly) generally is a 2D quiver plot (or vector plot, as can be seen here: http://en.wikipedia.org/wiki/File:VectorField.svg). This is a scatter plot with arrows pointing in certain directions instead of points. Quiver plots are highly useful in physics and in analysis of ordinary differential equations (and of course, I need one for my research :-) I consider Winston the first place to go to do my plotting, and having it supported here would increase the draw for undergraduate ODE teachers to turn to this great language for teaching support. I think it would be a big win for Julia if Winston supported this type of plot.

[lobingera]

something like #172 ?

You see x-y grid with 15 steps, random length and direction.

[abahm]

Yes! This would be great - perhaps it can be merged into the main repo.

On Tue, Sep 9, 2014 at 12:03 PM, Andreas Lobinger [email protected]
wrote:

something like #172 #172 ?

You see x-y grid with 15 steps, random length and direction.

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#171 (comment).

[lobingera]

A pull request is already the polite question to include the code into the main repo...

I never worked with quiver, is the interface x,y, direction, length OK?
Winston would have some infrastructure (i was impressed, that line color and line width didn't even need code from my side) to color the arrows also. Is this an option?
And for the style of the arrow, the current thing is just 3 lines, any better idea?

[abahm]

The quiver plot interfaces I've seen so far usually offer a (x, y, dx, dy)
interface where dx,dy are the offset from the x,y position that the head
of the arrow should land on, as opposed to (x,y,theta,r).

Perhaps it would be possible to include that interface as an option via
pairing up the xy as (v, dv)?

Secondarily, it would be nice to have the color and line width be
optionally vectors as well, so that multiple colors and scales of arrow are
possible.

I don't care too much about the arrow head style personally. But if there
is an easy way to offer variety, that would be nice for the community. It
could always be added later.

Thanks,
Alan

On Wed, Sep 10, 2014 at 1:39 AM, Andreas Lobinger [email protected]
wrote:

A pull request is already the polite question to include the code into the
main repo...

I never worked with quiver, is the interface x,y, direction, length OK?
Winston would have some infrastructure (i was impressed, that line color
and line width didn't even need code from my side) to color the arrows
also. Is this an option?
And for the style of the arrow, the current thing is just 3 lines, any
better idea?

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#171 (comment).

[nolta]

Yes, let's go with (x, y, dx, dy).