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HELP with ListPlotVectorField[]
Posted:
Sep 26, 1996 9:59 PM


About a week or two ago I posted a similar problem, so please read through or ignore upon your interest!
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!!!!!
Thank's in advance,
David A. Johnson



