<div dir="ltr">Hi list, <div><br></div><div>first, i'm new with grass </div><div><br></div><div>Im trying to do some math calculations with r.mapcalc, but my result allways is nan. </div><div><br></div><div>When I display the image I can see different values, not only nan.<br></div><div><br></div><div>Thanks</div><div><br></div><div><br></div><div><br></div><div><div>GRASS 7.1.svn (sequia):/opt/grass_trunk/bin.x86_64-unknown-linux-gnu > <a href="http://r.info">r.info</a> NDVI_1_h11v11</div><div><br></div><div> +----------------------------------------------------------------------------+</div><div> | Map:      NDVI_1_h11v11                  Date: Mon Dec  1 05:12:28 2014    |</div><div> | Mapset:   sequia                         Login of Creator: polzader        |</div><div> | Location: sequia                                                           |</div><div> | DataBase: /home/polzader/Documentos/grassdata_diana_bpr                    |</div><div> | Title:     ( NDVI_1_h11v11 )                                               |</div><div> | Timestamp: none                                                            |</div><div> |----------------------------------------------------------------------------|</div><div> |                                                                            |</div><div> |   Type of Map:  raster               Number of Categories: 0               |</div><div> |   Data Type:    DCELL                                                      |</div><div> |   Rows:         4409                                                       |</div><div> |   Columns:      7499                                                       |</div><div> |   Total Cells:  33063091                                                   |</div><div> |        Projection: Latitud - Longitud.                                     |</div><div> |            N: 19:54:02.16S    S: 30:01:58.200271S   Res: 0:00:08.273087    |</div><div> |            E: 63:35:44.521118W    W: 80:49:44.4W   Res: 0:00:08.273087     |</div><div> |   Range of data:    min = -2000  max = 9090                                |</div><div> |                                                                            |</div><div> |   Data Description:                                                        |</div><div> |    generated by r.series                                                   |</div><div> |                                                                            |</div><div> |   Comments:                                                                |</div><div> |    r.series input="MOD13Q1.A2004001.h11v11.005.2007235231758.250m_16_da\   |</div><div> |   ys_NDVI,MOD13Q1.A2005001.h11v11.005.2007352072715.250m_16_days_NDVI,\   |</div><div> |    MOD13Q1.A2006001.h11v11.005.2008064055525.250m_16_days_NDVI,MOD13Q1.\   |</div><div> |    A2007001.h11v11.005.2007021105928.250m_16_days_NDVI,MOD13Q1.A2008001\   |</div><div> |    .h11v11.005.2008019102106.250m_16_days_NDVI,MOD13Q1.A2009001.h11v11.\   |</div><div> |    005.2009019230008.250m_16_days_NDVI,MOD13Q1.A2010001.h11v11.005.2010\   |</div><div> |    027061330.250m_16_days_NDVI,MOD13Q1.A2011001.h11v11.005.201102405534\   |</div><div> |    0.250m_16_days_NDVI,MOD13Q1.A2012001.h11v11.005.2012019103715.250m_1\   |</div><div> |    6_days_NDVI,MOD13Q1.A2013001.h11v11.005.2013018034332.250m_16_days_N\   |</div><div> |    DVI,MOD13Q1.A2014001.h11v11.005.2014018092301.250m_16_days_NDVI,MOD1\   |</div><div> |    3Q1.A2004017.h11v11.005.2008224113415.250m_16_days_NDVI,MOD13Q1.A200\   |</div><div> |    5017.h11v11.005.2007353093413.250m_16_days_NDVI,MOD13Q1.A2006017.h11\   |</div><div> |    v11.005.2008278011906.250m_16_days_NDVI,MOD13Q1.A2007017.h11v11.005.\   |</div><div> |    2007096165508.250m_16_days_NDVI,MOD13Q1.A2008017.h11v11.005.20080370\   |</div><div> |    54317.250m_16_days_NDVI,MOD13Q1.A2009017.h11v11.005.2009035200807.25\   |</div><div> |    0m_16_days_NDVI,MOD13Q1.A2010017.h11v11.005.2010036002816.250m_16_da\   |</div><div> |    ys_NDVI,MOD13Q1.A2011017.h11v11.005.2011039201212.250m_16_days_NDVI,\   |</div><div> |    MOD13Q1.A2012017.h11v11.005.2012046172118.250m_16_days_NDVI,MOD13Q1.\   |</div><div> |    A2013017.h11v11.005.2013039191638.250m_16_days_NDVI,MOD13Q1.A2014017\   |</div><div> |    .h11v11.005.2014038143732.250m_16_days_NDVI" output="NDVI_1_h11v11" \   |</div><div> |    method="average"                                                        |</div><div> |                                                                            |</div><div> +----------------------------------------------------------------------------+</div><div><br></div><div>GRASS 7.1.svn (sequia):/opt/grass_trunk/bin.x86_64-unknown-linux-gnu > <a href="http://r.info">r.info</a> NDWI_1_h11v11</div><div> +----------------------------------------------------------------------------+</div><div> | Map:      NDWI_1_h11v11                  Date: Mon Dec  1 05:49:38 2014    |</div><div> | Mapset:   sequia                         Login of Creator: polzader        |</div><div> | Location: sequia                                                           |</div><div> | DataBase: /home/polzader/Documentos/grassdata_diana_bpr                    |</div><div> | Title:     ( NDWI_1_h11v11 )                                               |</div><div> | Timestamp: none                                                            |</div><div> |----------------------------------------------------------------------------|</div><div> |                                                                            |</div><div> |   Type of Map:  raster               Number of Categories: 0               |</div><div> |   Data Type:    DCELL                                                      |</div><div> |   Rows:         4409                                                       |</div><div> |   Columns:      7499                                                       |</div><div> |   Total Cells:  33063091                                                   |</div><div> |        Projection: Latitud - Longitud.                                     |</div><div> |            N: 19:54:02.16S    S: 30:01:58.200271S   Res: 0:00:08.273087    |</div><div> |            E: 63:35:44.521118W    W: 80:49:44.4W   Res: 0:00:08.273087     |</div><div> |   Range of data:    min = -9254.65838509317  max = 9247.07852234276        |</div><div> |                                                                            |</div><div> |   Data Description:                                                        |</div><div> |    generated by r.mapcalc                                                  |</div><div> |                                                                            |</div><div> |   Comments:                                                                |</div><div> |    (NIR_reflectance_1_h11v11 - MIR_reflectance_1_h11v11) /                 |</div><div> |    (NIR_reflectance_1_h11v11 + MIR_reflectance_1_h11v11) * 10000           |</div><div> |                                                                            |</div><div> +----------------------------------------------------------------------------+</div><div><br></div><div><br></div><div>r.mapcalc --o expression="bla=NDVI_1_h11v11 - NDWI_1_h11v11"</div><div>GRASS 7.1.svn (sequia):/opt/grass_trunk/bin.x86_64-unknown-linux-gnu > <a href="http://r.info">r.info</a> bla</div><div> +----------------------------------------------------------------------------+</div><div> | Map:      bla                            Date: Mon Dec  8 18:04:41 2014    |</div><div> | Mapset:   sequia                         Login of Creator: polzader        |</div><div> | Location: sequia                                                           |</div><div> | DataBase: /home/polzader/Documentos/grassdata_diana_bpr                    |</div><div> | Title:     ( bla )                                                         |</div><div> | Timestamp: none                                                            |</div><div> |----------------------------------------------------------------------------|</div><div> |                                                                            |</div><div> |   Type of Map:  raster               Number of Categories: 0               |</div><div> |   Data Type:    DCELL                                                      |</div><div> |   Rows:         2861                                                       |</div><div> |   Columns:      9350                                                       |</div><div> |   Total Cells:  26750350                                                   |</div><div> |        Projection: Latitud - Longitud.                                     |</div><div> |            N: 49:42:30.96S    S: 60:04:18.329421S   Res: 0:00:13.039975    |</div><div> |            E: 46:24:51.430659W    W: 80:16:55.2W   Res: 0:00:13.039975     |</div><div> |   Range of data:    min = -nan  max = -nan                                 |</div><div> |                                                                            |</div><div> |   Data Description:                                                        |</div><div> |    generated by r.mapcalc                                                  |</div><div> |                                                                            |</div><div> |   Comments:                                                                |</div><div> |    NDVI_1_h11v11 - NDWI_1_h11v11                                    </div><div> |                                                                            |</div><div> +----------------------------------------------------------------------------+</div></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr">Diana Marcela Brito Hoyos<div>Biologa</div><div><a href="mailto:d.brito@javeriana.edu.co" target="_blank">d.brito@javeriana.edu.co</a></div><div><br></div><div><br></div></div></div>
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