#2098: i.vi gari wrong formula?
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Reporter: kristinah | Owner: grass-dev@…
Type: defect | Status: new
Priority: normal | Milestone: 6.4.4
Component: Default | Version: unspecified
Keywords: | Platform: Unspecified
Cpu: All |
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The formula for GARI in the manual
(http://grass.osgeo.org/grass70/manuals/i.vi.html) seems to be wrong. As
it is now, the result would always be 1.
It is
"
GARI = ( nirchan - (greenchan-(bluechan - redchan))) /
( nirchan- (greenchan-(bluechan - redchan)))
"
It should be (e.g. according to
http://www.indexdatabase.de/db/i-single.php?id=363)
"
GARI = ( nirchan - (greenchan-(bluechan - redchan))) /
( nirchan- (greenchan+(bluechan - redchan)))
"
As the formula in the manual seems to be taken from code, the code might
be wrong as well. I did not test the function, only read the manual
online.
--
Ticket URL: <https://trac.osgeo.org/grass/ticket/2098>
GRASS GIS <http://grass.osgeo.org>
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