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Re: Vector representation of data. [message #83672]

Fri, 29 March 2013 14:18

chris_torrence@NOSPAM is currently offline

chris_torrence@NOSPAM
Messages: 528
Registered: March 2007

Senior Member

On Wednesday, March 27, 2013 8:04:24 AM UTC-6, dave poreh wrote:
> Folks
>
> Hi,
>
> I have data like x,y, z and z shows my intensity data (x and y are like coordinates). My data has low value in one corner and i was thinking maybe I could show the data like vectors; length of vector should show ||z|| and direction toward the lowest point in my 2D data (x-y). Can someone give me an idea about how could I do that please?
>
> Cheers,
>
> Dave

Hi Dave,

You should be able to use the VECTOR function to create the actual vector plot. You just need to compute the "U" and "V" components of the vectors, along with the X and Y locations. Then it is just:

v = VECTOR(U, V, X, Y)

The trick will be computing your angles, perhaps by computing some sort of "gradient" along your data? If you could get ||Z|| and angle Theta on a 2D grid, then you could just use:
U = ||Z|| cos(Theta)
V = ||Z|| sin(Theta).

Hope this helps a bit.

Cheers,
Chris
ExelisVIS

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[Message index]

		Re: Vector representation of data. By: chris_torrence@NOSPAM on Fri, 29 March 2013 14:18
		Re: Vector representation of data. By: Phillip Bitzer on Fri, 29 March 2013 16:38
		Re: Vector representation of data. By: d.poreh on Thu, 04 April 2013 00:27

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