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Showing posts from December, 2010

Open spatial software and others

For anyone just starting out in OPEN GIS or spatial technologies in general its hard to find the wright tools/software for the job. Here is a list of free and some open source, software (not just spatial ones) I use all the time. Database: Postgresql with PostGIS Desktop GIS: Quantum GIS Web Map Server: Geoserver Web Map Javascript Library: Openlayers Web Rich Internet Application (RIA): ExtJS Web Map RIA: Geoext Web Map environment: Opengeo Google Earth Spatial Libraries: FWTools , Geotools OpenStreetMap Import to Postgresql: osm2pgsql Windows Mobile 5.x, 6.x OSM data collection: osmtracker Scripting Languages: Python , Javascript Desktop Graphics: Inkscape (vector), GIMP (raster) Mind Mapping: FreeMind Screen capure: Greenshot (windows only) Text editor: Notepad++ (windows only) Versioning subversion: Tortoise SVN (windows) Virtual Machines: VMWare Player Operating Systems: Windows 7 and Ubuntu 10.10 Windows Explorer: Total Commander Organizi

Postgresql pgagent Windows 7 32bit trouble starting service

Another adventure with datbase stuff.  I have a new machine and need to back up my Postgresql/PostGIS databases and want to use PGAGENT.  I have used my trusty .bat files and windows scheduler up until now and just want to try something new. First I read the great post from postgresonline journal Setting up PgAgent and Doing Scheduled Backups.   Its old 2008 but no matter. So I followed all the steps and then damm.. Trouble getting pgagent to start.  On my German machine this nice error shows when I try to start the service/dienst " Dienst "PostgreSQL Scheduling Agent - pgagent" wurde auf "Lokaler Computer" gestartet und dann angehalten. Einige Dienste werden automatisch angehalten, wenn sie nicht von anderen Diensten oder Programmen verwendet werden."   This basically says screw you because of one or more of the following causes: wrong username wrong password user has no access privaleges to the db user has no wrights to execute stuf So I check th

Transform OSM data to epsg: 4326 known as wgs84

 The data is already in my Postgresql PostGIS set up using the osm2pgsql.exe to load it.  You can of course specify other EPSG codes upon loading, but it seems to "not work" all the time so I prefer to go with the defaults then transform my data.   Spatialreference.org  is your best bet for more info. This is the SQL I used to create a new column to store the OSM data in WGS84 or EPSG 4326.  Be sure to change the bits you need for your data. --Transforming to Another spatial reference system --first we create a new column to hold the new geometry in the new projection SELECT AddGeometryColumn( 'planet_osm_line', 'geom_wgs84', 4326, 'LINESTRING', 2); -- now we populate the new column with the transformed data using: -- transform(geometrycol, new EPSG) UPDATE planet_osm_line SET geom_wgs84 = transform(way, 4326); --Transforming to Another spatial reference system --first we create a new column to hold the new geometry in the

OSM data to shapefile with specific OSM Tags

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Well I had a unique problem or I should say not so unique problem in preparing some OpenStreetMap (OSM) data for import into PostGIS and then export to Shapefiles for my students. Job at hand: Generate some shapefiles based on specific OSM data tags more specifically wheelchair access tags. Tools: osm2pgsql.exe python 3.1 custom script see below pgsql2shp.exe  this is installed with PostGIS located in the /bin  directory Prerequisites: Postgresql 8.4.4 with PostGIS 1.5.2 Download and unzip the osm2pgsql .exe for import Windows 7 Pro  (this is not a prereq, just letting you know what I used) Procedure : Download OSM data as .osm for your region using the web tab "Export" on the osm website (see screenshot) or visit GeoFabrik or Cloudmade for shapefiles/OSM data. Prepare data for osm2pgsql.exe by  Edit the import   .style file  to limit what is actually going into PostGIS so only our needed fields come across.  See the wiki page for details Edit the .osm fil

ArcGIS 9.3 FME import shapefile into Postgresql PostGIS

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Here is the task that I am tackling or I should say finished tackling. Import some Shapefiles into an already existing Postgresql / PostGIS database schema called "demo" (not public schema) with already existing tables for each shapefile that have predefined fields but are lacking any data what so ever. Basically I’m importing only 2 fields one is the geometry column aka the actual geometry of the data in the shapefile and one field with attribute data. Prerequisits: Postgresql 8.4 with PostGIS 1.4 or 1.5 installed on local machine (I'm using Win 7 Pro) ArcGIS 9.3 with FME  Interoperability Extension enabled Lets get started:  First firing up my trusty ArcCatalog 9.3 I created a new “Spatial ETL Tool” to handle the work (Right Click an existing Toolbox  select create new.create new Spatial ETL ).  Then following the instructions filling in the source files and specifying the Postgresql PostGIS database on my localhost as the destination all things

How to calculate the length value for a field in QGIS

Really I should have titled this article. " How to create a shapefile with a field to store length values and then fill the field with length values using Quantum GIS aka.  QGIS " NOTES: - Using Quantum GIS 1.7 r14693  from the osgeo4w-setup.exe - OS  Windows 7 Professional 32 bit - example will use EPSG 31258 but you can of course use your own local EPSG code. - Generally I already have some other data in EPSG 31258 I use as background data so I can see where my new file is in the world.  When QGIS starts it has a default location of 0.00 x  and  0.00 y at the center of your map window which = no where in particular.  You should then define your project coordinate system under Settings >  Project Properties > tab coordiate reference systems and set to EPSG 31258. For more funky spatial reference EPSG  fun check out   spatialreference.org Part 1. Creating an empty Shapefile to store our data with lengths. Open Quantum GIS Go to Layer > New > New