[GRASS5] Strange r.mapcalc behaviour - bug?
Markus Neteler
neteler at itc.it
Mon Mar 22 09:38:00 EST 2004
Hi,
there seems to be a problem with / in r.mapcalc:
g.region rast=modis_vi250m_16_days_NDVI -p
projection: 99 (Transverse Mercator)
zone: 0
datum: rome40
ellipsoid: international
north: 5232499.37200598
south: 5050874.37200598
west: 1593200.7883525
east: 1801075.7883525
nsres: 125
ewres: 125
rows: 1453
cols: 1663
r.support -r modis_vi250m_16_days_NDVI
Updating the stats for [modis_vi250m_16_days_NDVI]
Updating the number of categories for [modis_vi250m_16_days_NDVI]
r.info -r modis_vi250m_16_days_NDVI
min=0
max=36748
#now I want to get the typical range for NDVI: -1.0 .. 1.0
#values above will be filtered away later:
r.mapcalc "modis_vi250m_16_days_NDVI.2=1. * modis_vi250m_16_days_NDVI / 10000."
r.support -r modis_vi250m_16_days_NDVI.2
Updating the stats for [modis_vi250m_16_days_NDVI.2]
Updating the number of categories for [modis_vi250m_16_days_NDVI.2]
r.info -r modis_vi250m_16_days_NDVI.2
min=0.000000
max=4.000000
#############
The same happens when not using r.support.
It seems to round to integer internally? Or I am missing something else.
Markus
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