[GRASS-dev] [GRASS GIS] #2098: i.vi gari wrong formula?

[GRASS GIS]

#2098: i.vi gari wrong formula?
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  Reporter:  kristinah    |       Owner:  grass-dev@…              
      Type:  defect       |      Status:  closed                   
  Priority:  normal       |   Milestone:  7.0.0                    
 Component:  Imagery      |     Version:  svn-trunk                
Resolution:  fixed        |    Keywords:  i.vi                     
  Platform:  Unspecified  |         Cpu:  All                      
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Changes (by lucadelu):

  * status:  reopened => closed
  * resolution:  => fixed


Comment:

 Replying to [comment:3 kristinah]:
 > Actually, the formula I provided was also wrong. The correct formula has
 the "+" in a different position
 >
 > GARI = ( nirchan - (greenchan- (bluechan - redchan))) /
 > ( nirchan + (greenchan - (bluechan - redchan)))
 >
 > This was taken from the article where the formula was actually defined:
 > Gitelson, Anatoly A.; Kaufman, Yoram J.; Merzlyak, Mark N. (1996)
 > Use of a green channel in remote sensing of global vegetation from EOS-
 MODIS
 > Remote Sensing of Environment 58 (3), 289-298.
 > DOI: 10.1016/s0034-4257(96)00072-7
 >
 > When reading the explanation about the meaning of the index in this
 article, it became clear to me, that "indexdatabase.de" must be wrong.
 >
 > Sorry for pointing you in the wrong direction first!
 >

 I update GARI formula in i.vi and related documentation in r58389
 I close the ticket, please reopen if needed

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Ticket URL: <http://trac.osgeo.org/grass/ticket/2098#comment:4>
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