Not sure that will give you a solution, but an r.mapcalc expression in grass 7.1 should look like:
r.mapcalc --overwrite expression="bla = NDVI_1_h11v11 - NDWI_1_h11v11" In other words 1) the --o flag in grass 6.4 was changed to --overwrite in grass 7 and higher, and 2) there should be a space before the first *=* sign. Check out: http://grass.osgeo.org/grass71/manuals/r.mapcalc.html Paulo On Mon, Dec 8, 2014 at 10:23 PM, Diana Brito <dianisbri...@gmail.com> wrote: > Hi list, > > first, i'm new with grass > > Im trying to do some math calculations with r.mapcalc, but my result > allways is nan. > > When I display the image I can see different values, not only nan. > > Thanks > > > > GRASS 7.1.svn (sequia):/opt/grass_trunk/bin.x86_64-unknown-linux-gnu > > r.info NDVI_1_h11v11 > > > > +----------------------------------------------------------------------------+ > | Map: NDVI_1_h11v11 Date: Mon Dec 1 05:12:28 2014 > | > | Mapset: sequia Login of Creator: polzader > | > | Location: sequia > | > | DataBase: /home/polzader/Documentos/grassdata_diana_bpr > | > | Title: ( NDVI_1_h11v11 ) > | > | Timestamp: none > | > > > |----------------------------------------------------------------------------| > | > | > | Type of Map: raster Number of Categories: 0 > | > | Data Type: DCELL > | > | Rows: 4409 > | > | Columns: 7499 > | > | Total Cells: 33063091 > | > | Projection: Latitud - Longitud. > | > | N: 19:54:02.16S S: 30:01:58.200271S Res: 0:00:08.273087 > | > | E: 63:35:44.521118W W: 80:49:44.4W Res: 0:00:08.273087 > | > | Range of data: min = -2000 max = 9090 > | > | > | > | Data Description: > | > | generated by r.series > | > | > | > | Comments: > | > | r.series > input="MOD13Q1.A2004001.h11v11.005.2007235231758.250m_16_da\ | > | ys_NDVI,MOD13Q1.A2005001.h11v11.005.2007352072715.250m_16_days_NDVI,\ > | > | > MOD13Q1.A2006001.h11v11.005.2008064055525.250m_16_days_NDVI,MOD13Q1.\ | > | > A2007001.h11v11.005.2007021105928.250m_16_days_NDVI,MOD13Q1.A2008001\ | > | > .h11v11.005.2008019102106.250m_16_days_NDVI,MOD13Q1.A2009001.h11v11.\ | > | > 005.2009019230008.250m_16_days_NDVI,MOD13Q1.A2010001.h11v11.005.2010\ | > | > 027061330.250m_16_days_NDVI,MOD13Q1.A2011001.h11v11.005.201102405534\ | > | > 0.250m_16_days_NDVI,MOD13Q1.A2012001.h11v11.005.2012019103715.250m_1\ | > | > 6_days_NDVI,MOD13Q1.A2013001.h11v11.005.2013018034332.250m_16_days_N\ | > | > DVI,MOD13Q1.A2014001.h11v11.005.2014018092301.250m_16_days_NDVI,MOD1\ | > | > 3Q1.A2004017.h11v11.005.2008224113415.250m_16_days_NDVI,MOD13Q1.A200\ | > | > 5017.h11v11.005.2007353093413.250m_16_days_NDVI,MOD13Q1.A2006017.h11\ | > | > v11.005.2008278011906.250m_16_days_NDVI,MOD13Q1.A2007017.h11v11.005.\ | > | > 2007096165508.250m_16_days_NDVI,MOD13Q1.A2008017.h11v11.005.20080370\ | > | > 54317.250m_16_days_NDVI,MOD13Q1.A2009017.h11v11.005.2009035200807.25\ | > | > 0m_16_days_NDVI,MOD13Q1.A2010017.h11v11.005.2010036002816.250m_16_da\ | > | > ys_NDVI,MOD13Q1.A2011017.h11v11.005.2011039201212.250m_16_days_NDVI,\ | > | > MOD13Q1.A2012017.h11v11.005.2012046172118.250m_16_days_NDVI,MOD13Q1.\ | > | > A2013017.h11v11.005.2013039191638.250m_16_days_NDVI,MOD13Q1.A2014017\ | > | .h11v11.005.2014038143732.250m_16_days_NDVI" output="NDVI_1_h11v11" > \ | > | method="average" > | > | > | > > > +----------------------------------------------------------------------------+ > > GRASS 7.1.svn (sequia):/opt/grass_trunk/bin.x86_64-unknown-linux-gnu > > r.info NDWI_1_h11v11 > > > +----------------------------------------------------------------------------+ > | Map: NDWI_1_h11v11 Date: Mon Dec 1 05:49:38 2014 > | > | Mapset: sequia Login of Creator: polzader > | > | Location: sequia > | > | DataBase: /home/polzader/Documentos/grassdata_diana_bpr > | > | Title: ( NDWI_1_h11v11 ) > | > | Timestamp: none > | > > > |----------------------------------------------------------------------------| > | > | > | Type of Map: raster Number of Categories: 0 > | > | Data Type: DCELL > | > | Rows: 4409 > | > | Columns: 7499 > | > | Total Cells: 33063091 > | > | Projection: Latitud - Longitud. > | > | N: 19:54:02.16S S: 30:01:58.200271S Res: 0:00:08.273087 > | > | E: 63:35:44.521118W W: 80:49:44.4W Res: 0:00:08.273087 > | > | Range of data: min = -9254.65838509317 max = 9247.07852234276 > | > | > | > | Data Description: > | > | generated by r.mapcalc > | > | > | > | Comments: > | > | (NIR_reflectance_1_h11v11 - MIR_reflectance_1_h11v11) / > | > | (NIR_reflectance_1_h11v11 + MIR_reflectance_1_h11v11) * 10000 > | > | > | > > > +----------------------------------------------------------------------------+ > > > r.mapcalc --o expression="bla=NDVI_1_h11v11 - NDWI_1_h11v11" > GRASS 7.1.svn (sequia):/opt/grass_trunk/bin.x86_64-unknown-linux-gnu > > r.info bla > > > +----------------------------------------------------------------------------+ > | Map: bla Date: Mon Dec 8 18:04:41 2014 > | > | Mapset: sequia Login of Creator: polzader > | > | Location: sequia > | > | DataBase: /home/polzader/Documentos/grassdata_diana_bpr > | > | Title: ( bla ) > | > | Timestamp: none > | > > > |----------------------------------------------------------------------------| > | > | > | Type of Map: raster Number of Categories: 0 > | > | Data Type: DCELL > | > | Rows: 2861 > | > | Columns: 9350 > | > | Total Cells: 26750350 > | > | Projection: Latitud - Longitud. > | > | N: 49:42:30.96S S: 60:04:18.329421S Res: 0:00:13.039975 > | > | E: 46:24:51.430659W W: 80:16:55.2W Res: 0:00:13.039975 > | > | Range of data: min = -nan max = -nan > | > | > | > | Data Description: > | > | generated by r.mapcalc > | > | > | > | Comments: > | > | NDVI_1_h11v11 - NDWI_1_h11v11 > | > | > > > +----------------------------------------------------------------------------+ > > > > > > > > > > > > > > > > -- > Diana Marcela Brito Hoyos > Biologa > d.br...@javeriana.edu.co > > > > _______________________________________________ > grass-user mailing list > grass-user@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/grass-user >
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