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Re: WHERE Function [message #4239 is a reply to message #4152]

Thu, 11 May 1995 00:00

chris
Messages: 22
Registered: October 1994

Junior Member

PRYHODA (bjp8350@osfmail.isc.rit.edu) wrote:
: I am using the WHERE function to return the pixel locations of a single object
: in a binary image. The WHERE function returns a LONGWORD VECTOR that can be
: used to subscript the image array. I need to calculate the distance between
: each combination of border pixels to find the object's major axis.

: How can I seperate the LONGWORD VECTOR into its X and Y components? so I can
: use the distance formula. Or is there an easier way to find the distance
: between each pixel?

There is probably an easier way, but here's how you can find x and y.

Nx = 4 & Ny = 10 ; Dimensions of the Array
im = findgen(Nx) # findgen(Ny) ; Make an arbitrary array.
w = where( im eq 27) ; w = longword type
x = w mod Nx
y = w / Nx
print, im(x,y) ; check: should = 27.

You might consider playing with the dist(_) function, or with
shift.

-chris

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[Message index]

		WHERE Function By: bjp8350 on Wed, 10 May 1995 00:00
		Re: WHERE Function By: rivers on Fri, 12 May 1995 00:00
		Re: WHERE Function By: chris on Thu, 11 May 1995 00:00
		Re: WHERE Function By: chase on Thu, 11 May 1995 00:00
		Re: where function By: jeanh on Sun, 23 January 2011 13:12

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