RE: [Tcl-nap-users] Missing values

[<Pet...@cs...>]

Hi Sala,

        nap ndvi =3D 0.0/0.0=20

         $ndvi
         _

  This sets x to NaN (not a number)  1.0/0.0  generates Inf. The default
missing value for float is NaN.=20

You could use

nap ndvi =3D isnan(ndvi) ? maxval : ndvi


to fix the problem

Cheers

Peter T

		-----Original Message-----
		From: tcl...@li...
[mailto:tcl...@li...] On Behalf Of salah
jubeh
		Sent: Monday, 13 March 2006 8:32 PM
		To: NAP
		Subject: [Tcl-nap-users] Missing values

		Hi all
		=20
		While doing some image analysis i did NDVI
"near-red/near+red" , some pixel values of  both images has zero value
thats mean (0-0)/(0-0)  afetr thai i trid to get the max but i get a
strange result.
		=20
		how can i get the max value in that case.
		=20
		 =20
		=20
		=20

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