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Topic: HELP with ListPlotVectorField[]
Replies: 0

 dave@siqin.feinberg.nwu.edu Posts: 2 Registered: 12/11/04
HELP with ListPlotVectorField[]
Posted: Sep 26, 1996 9:59 PM

I need help with ListPlotVectorField[] or recreating a variation of it.

What I would ideally like is to have options to ListPlotVectorField[] that are a list that can vary the radius of a circle drawn around the head of each vector arrow head. Also I'd like an option that would be a list that could vary the grayscale or color of each vector.

What I'm doing is summing many vector fields and I would like the radius of the circles to represent the standard deviation of that particular vectors elements.

something like (please forgive the ASCII graphics)

( ^ )
/ ------
/ ( ^ )
/ \
/ \
/ \

What I've tried is something like this:
vectorMatrix = {};
Do[
g = {
Arrow[{x,y}, {x2,y2}],
Line[{{x,y}, {x2, y2}}],
GrayLevel[sd[[x]][[j]] ],
Circle[{x2,y2}, sd[[x]][[y]] ]
};
vectorMatrix = Append[vectorMatrix, g];
,{x, 1, noColumns}, {y, 1, noRows}]
Show[Graphics[vectorMatrix]]

Unfortunately the visual look is not correct and that's where I'd like some help. {x2,y2} are a value that represents a vector (x,y) whose origin is at (0,0).

I have a web page set up with the actual Mma code at http://siqin.feinberg.nwu.edu/Served/tmp/myVectorPlot.html
I know my code is terrible so please resist the temptation to slam me. I am not very familiar with Mma programming particularly with its graphics primitives so please HELP!!!!!