[[Image(source:EDA/data/Docs/trac/gdal.jpg)]] = Using GDAL - Geospatial Data Abstraction Library and rgdal = ---- back to Recipes for EDA ["CookBook Eda"] = gdal = ---- gdal url:[http://www.gdal.org/][[BR]] is a translator library for raster geospatial data formats that is released under an X/MIT style Open Source license by the Open Source Geospatial Foundation. As a library, it presents a single abstract data model to the calling application for all supported formats. It also comes with a variety of useful commandline utilities for data translation and processing. [[BR]] '' Cédric => What I've found at this site is not really helpfull, it is only python and c++ code. ''[[BR]] url:[http://www.bostongis.com/?content_name=ogr_cheatsheet] => '' Cedric: very good site ! '' [[BR]] url:[http://trac.osgeo.org/gdal/] '' Cedric : not really usefull '' ''' Below we suppose that you have the Qgis tool installed, so your path is C:\OSGeo4W ''' Qgis has gdal included. Gdal comes with two main tools (executable files), the files for gdal are in {{{ C:\OSGeo4W\share\gdal }}} call >cmd {{{ C:\OSGeo4W\bin\ogr2ogr }}} or {{{ C:\OSGeo4W\bin\ogrinfo }}} === Translating .mdb into shapes outside ESRI === ---- {{{ C:\OSGeo4W\bin\ogr2ogr -f "ESRI Shapefile" C:\base\basesig\Czhyd.shp C:\base\basesig\Czhyd.mdb }}} '' Cedric : this one works but warning there should be no space in the path (ex : no "document and settings/"...) '' === Conversion from PostGIS to ESRI Shape === '' adapted from url: ''[http://www.bostongis.com/?content_name=ogr_cheatsheet] The '''pgsql2shp''' and '''shp2pgsql''' are usually the best tools for converting back and forth between PostGIS and ESRI for 2 main reasons. * ''It has fewer idiosyncracies when converting data.'' * ''It has a lot fewer dependencies so can fit on your floppy.'' If you really want to use Ogr2Ogr for this kind of conversion, below is the standard way to do it Here the example should export the table riversegments[[BR]] Cedric {{{ C:\OSGeo4W\bin\ogr2ogr -f "ESRI Shapefile" C:\base\basesig\essai.shp PG:"host=localhost user=postgres dbname=CCM password=postgres port=5433" "riversegments" }}} Celine (pwd to be precised) {{{ C:\OSGeo4W\bin\ogr2ogr -f "ESRI Shapefile" C:\base\basesig\essai.shp PG:"host=localhost user=postgres dbname=CCM password=PWD" "riversegments" }}} '' Cedric : celui ci marche mais j'ai eu du mal, ne marche pas une deuxième fois si les shape sont déjà crées dans le répertoire ''[[BR]] {{{ C:\OSGeo4W\bin\ogr2ogr -f "ESRI Shapefile" C:\base\basesig\essai PG:"host=localhost user=postgres dbname=CCM password=postgres port=5433" "riversegments" }}} '' Cedric : OK marche de nouveau ''[[BR]] '''Selecting specific fields, sets of data and Geometry'''[[BR]] Sometimes you have more than one geometry field in a table, and ESRI shape can only support one geometry field per shape. Also you may only want a subset of data. In these cases, you will need to select the geometry field to use. The most flexible way to do this is to use the -sql command which will take any sql statement. {{{ C:\OSGeo4W\bin\ogr2ogr -f "ESRI Shapefile" C:\base\basesig\essai1 PG:"host=locahost user=postgres dbname=CCM password=postgres port=5433" -sql "SELECT gid, the_geom FROM riversegments" }}} '' Cedric : ne marche pas, j'obtiens un message du type Unable to open datasource with following drivers, celui là on l'a très très souvent, j'ai essayé plusieurs trucs je ne comprends pas, la requete marche dans pgadmin''[[BR]] ''' One way in which ogr2ogr excels above using the pgsql2shp tool is that ogr2ogr can export multiple tables at once. This is pretty handy for sharing your postgis data with others who do not have a postgis database. ''' The code below will export all your postgis tables out into a folder called mydatadump in ESRI shape (shp) format. {{{ C:\OSGeo4W\bin\ogr2ogr -f "ESRI Shapefile" essai2 PG:"host=locahost user=postgres dbname=CCM password=postgres port=5433" }}} Now most of the time you probably only want to output a subset of your postgis tables rather than all your tables. This code exports only the riversegments and rivernodes tables to a folder called c:/base/basesig/mydatadump in ESRI shapefile format {{{ C:\OSGeo4W\bin\ogr2ogr -f "ESRI Shapefile" c:/base/basesig/mydatadump PG:"host=localhost user=postgres dbname=CCM password=postgres port=5433" riversegments rivernodes }}} '' Cedric Celui là marche même si il n'y a pas de guillemet" = Connecting PostGIS with R using Rgdal = ---- The principal idea is that we insert monitoring network data in PostGIS, and then call R with an appropriate script, which includes information on what the data are called in the PostGIS data base. Users may also be interested in PL/R which allows R functions to be embedded within Postgres, and accessed directly as SQL commands...[[BR]] '' Cédric : Il semble que gdal ait été utilisé pour se connecter au projet inamap, et la page la plus intéressante (la seule qu'on trouve sur les forums) est la suivante url: [http://wiki.intamap.org/index.php/PostGIS] et bien sûr ça marche pas '' [[BR]] Run in R {{{ require(rgdal) readOGR(dsn="PG:host=localhost dbname=CCM user=postgres passwd=postgres port=5433",layer="riversegments") }}} which ressembles the site's script returns {{{ > require(rgdal) Le chargement a nécessité le package : rgdal Le chargement a nécessité le package : sp Geospatial Data Abstraction Library extensions to R successfully loaded Loaded GDAL runtime: GDAL 1.6.2, released 2009/07/31 Path to GDAL shared files: C:/Program Files/R/R-2.10.0/library/rgdal/gdal Loaded PROJ.4 runtime: Rel. 4.6.1, 21 August 2008 Path to PROJ.4 shared files: C:/Program Files/R/R-2.10.0/library/rgdal/proj Message d'avis : le package 'sp' a été compilé avec la version R 2.10.1 > readOGR(dsn="PG:host=localhost dbname=CCM user=postgres passwd=postgres port=5433",layer="riversegments") Erreur dans ogrInfo(dsn = dsn, layer = layer, input_field_name_encoding = input_field_name_encoding) : Cannot open file }}} Similar content in rgal library in R but with less support[[BR]] help for rgdal package[[BR]] url:[file:///C:/Program%20Files/R/R-2.10.0/library/rgdal/html/00Index.html][[BR]] [[BR]] Céline : "J'ai recherché dans mes bouquin et sur le Applied Spatial Data Analysis with R de Roger Bivand dont tu peux retrouver (une partie) des codes sur ce site" : url:[http://www.asdar-book.org/] Plus précisément sur cette page url:[http://www.asdar-book.org/book/die.R] ou à url:[http://www.asdar-book.org/book/die_mod.R]