[GRASS-user] problems with r.mapcalc

Diana_Brito · December 8, 2014, 9:23pm

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

···

Diana Marcela Brito Hoyos
Biologa
d.brito@javeriana.edu.co

Benjamin_Ducke1 · December 8, 2014, 9:47pm

Look closely at the output of r.info:
Your current region is not where your data is.

First change the region to the extent and
resolution of the input map(s):

g.region rast=NDVI_1_h11v11

... then run your r.mapcalc command.

Best,

Ben

On 08/12/14 22:23, Diana Brito 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 <http://r.info> grass-user@lists.osgeo.org

+----------------------------------------------------------------------------+
| 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 <http://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 <http://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.brito@javeriana.edu.co <mailto:d.brito@javeriana.edu.co>

_______________________________________________
grass-user mailing list
grass-user@lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/grass-user

--
Dr. Benjamin Ducke
{*} Geospatial Consultant
{*} GIS Developer

Spatial technology for the masses, not the classes:
experience free and open source GIS at http://gvsigce.org

ecodiv · December 8, 2014, 9:47pm

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 <dianisbrito2@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.brito@javeriana.edu.co

grass-user mailing list
grass-user@lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/grass-user