A Spatial Reference System Identifier (SRID) is a unique value used to unambiguously identify projected, unprojected, and local spatial coordinate system definitions

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17
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6answers
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Shapefile PRJ to PostGIS SRID lookup table?

I was wondering if there is such a thing as an shapefile PRJ to PostGIS SRID lookup table? Something that can translate the most standard shapefile PRJ definitions into the likely SRID. When using ...
10
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3answers
1k views

Looking for a pythonic way to calculate the length of a WKT linestring

I was quite unsatisfied with Calculating Length of Linestrings in WGS84 in Miles. It kept me wondering if there is a more convenient, Pythonic way to calculate the length of a WKT linestring according ...
7
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1answer
1k views

How do I get a country border data set into my geography column?

I have a PostGis database with a multipolygon geography (as opposed to geometry) column. I'd like to fill it with the country border data available from ...
7
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1answer
115 views

Using customized Coordinate System for Archaeological site data

I don't know so much about coordinate systems... In my office we use to deal with spatial data coming from archaeological sites. Each site has its own x-y-z coordinate system (GCS). Three simple ...
6
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3answers
2k views

How to insert a GeoJSON polygon into a PostGIS table?

I need to insert a polygon from GeoJSON to my PostGIS table. This is how the SQL query looks like. INSERT INTO tablename (name, polygon) VALUES ( 'Name', ST_GeomFromGeoJSON ( { ...
6
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1answer
82 views

Postgis 2.1 Inconsistent with spatialreference.org

The County of Napa, California, uses a projection "NAD_1983_StatePlane_California_II_FIPS_0402_Feet"; for example their roads.prj file has: ...
6
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1answer
95 views

How do I change an existing srs in QGis?

I am showing postgis data with srid 28992 (Amersfoort / RD New). But when I plot the geospatial data on a map (with openlayers plugin), the data is shown a hunderd meters off because the datum shift ...
5
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4answers
518 views

What is Spatial Reference System in Laymans Language?

I am trying to understand the concept behind the Spatial Reference System, Why is it used and what is so specific about the number. I went through many definations and almost all went over my head. So ...
5
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2answers
1k views

What is the SRID of census.gov shapfiles?

I downloaded the county files from: http://www.census.gov/cgi-bin/geo/shapefiles2011/main I cannot figure out what SRID to use with them. When I am trying to generate a class file from ./manage.py ...
5
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1answer
98 views

Is there a way to determine the datum used when all you have is a lon and lat?

I have a dataset of US intersections from 2011 that I'm going to be using in a project together with data based in WGS84. Included in the CSV file is a variety of fields two of which are the lat and ...
4
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1answer
2k views

Transforming geometry coordinates from SRID 4326 to SRID 3011

In SQLServer geometry field, I want to change the coordinates of geometry from one spatial reference system to another spatial reference system (from SRID 4326 to SRID 3011) by using ST_Transform. But ...
4
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2answers
415 views

ST_Distance is not delivering right results

I want to calculate the distance between lat/lon points. I tried the following queries: Select ST_DISTANCE(ST_GeomFromText('POINT(-73.97923 40.75571)', 4326), ST_GeomFromText('POINT(-73.974509 ...
3
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1answer
1k views

How to get the coordinate system from a PostGIS database?

My question is probably amazinlgy stupid, but I can't find the answer myself. I would like to extract from a database the latitude and longitude of points. For now, I'm getting x(the_geom) and ...
3
votes
3answers
401 views

How to find SRID for random polygon?

I'm testing spatial database performance on a dataset. Spatial objects in this dataset (stored as WKT in a flat text file) are random valid polygons which have vertex coordinates (x,y) where 100,000> ...
3
votes
1answer
551 views

how to add a custom SRID to Spatialite

I'd like to create a spatialite database and load it with shapefiles using the Mississippi Transverse Mercator (MSTM) projection, but it doesn't have an EPSG definition in the spatialite library of ...
3
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1answer
212 views

How to mix coordinate systems in GeoDjango?

This is a beginner question about working with different coordinate systems in GeoDjango. I've got a GeoDjango object with a polygon field, stored as OSGB coordinates: class Region(models.Model): ...
3
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1answer
87 views

Strange exposure of a PostGIS layer in QGIS after importing OSM data into a database

I've imported a osm layer into my postgres/postgis database. osm2pqsql -E 3857 -c -S /usr/share/osm2pgsql/default.style -H localhost -W -d landslide -U postgres oberpfalz-latest.osm.bz2 During the ...
3
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1answer
193 views

PostGIS spatial reference ID (SRID) for regular cartesian coordinate system?

I would like to store a polygon as a set of 2D points represented as x, y coordinates of a Cartesian coordinate system. Which spatial reference can I use? Looking at my spatial_ref_sys table, all the ...
3
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1answer
525 views

add new SRID to sql server

Is it possible to add a new SRID to sql server 2012? I've tried insert into sys.spatial_reference_systems values (4938, 'GEOCCS["GDA94",DATUM["Geocentric Datum of Australia 1994",SPHEROID["GRS ...
3
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1answer
494 views

PostGIS 2.0 ST_Transform with Rasters cannot find custom SRID

I'm trying to calculate an average value in a buffer around a point. Given a raster in EPSG 4326 and a similar point, this is fine, except that the values will be skewed as they are not projected in ...
3
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0answers
160 views

Creating Ellipse in WGS84, but with metric parameters

I have the function --Ellipse(x,y,rx,ry,rotation,#of segments in 1/4 of ellipse) SELECT ST_Translate( ST_Rotate( ST_Scale( ST_Buffer(ST_Point(0,0), 0.5, $6), $3, $4), $5), $1, $2) I have points in ...
3
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0answers
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ArcGIS and SqlServer.Types: Does feature.Shape.SpatialReference.FactoryCode == srid?

I created a test implementation of the ESRI Geometry to WKT recipe provided by @SagebrushGIS. It seems to work great, but I'm wondering if the SRID value expected by Microsoft.SqlServer.Types ...
2
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2answers
2k views

ogr2ogr srs options: where is the well known definition determined?

In the ogr2ogr documentation it says that when using -a_srs srs_def: Srs_def can be a full WKT definition (hard to escape properly), or a well known definition (ie. EPSG:4326) or a file with a WKT ...
2
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1answer
6k views

How I get SRID from Geometry field

what is the function for getting SRID from Geometry field. I have inserted a shapefile into SQLServer table with Geometry field defined. I know the projection of shapefile is Swreff99_1800 ...
2
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2answers
69 views

ESRI projection to SRID?

I am looking at MapX and MapY coordinates. The docs say they are "truncated State Plane coordinates: NAD 1983 State Plane Louisiana South FIPS 1702 (US Feet)." I am trying to reproject into a common ...
2
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1answer
60 views

Problem while Reprojecting

When I try to transform geometries from SRID 2321 to 4326, the transformed coordinates are swapping. Why is this happening? Below are the details Source SRID - EPSG:2321 Source Data Projection ...
2
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1answer
50 views

PostGIS ST_Contains query returns null

I have a shapefile of all US States that I've imported into a table with a multipolygon geometry column. (SRID 4326) I perform a spatial query based on lat/lon to return the state abbreviation. This ...
2
votes
3answers
2k views

SQL Server Geometry to geography conversion

I have imported a number of Shape files from the ordnance survey using shape2SQL these have been imported as geometry however i would like to convert them to Geography and specifically to srid 4326 ...
2
votes
2answers
2k views

Problem when calculating longitude and latitude for points

I have a PostGIS database with SRID=900913 (Google Mercator) and I would like to know the latitude and longitude of points. I use this command: ST_X(ST_TRANSFORM(the_geom,4283)) Following what is ...
2
votes
3answers
337 views

which map projection should I use to calculate distance in Poland

I'm using/learning geodjango + postgis, and I'm trying to calculate distance between 2 cities in Poland. First using WGS84/4326 I define 2 points, and then after transforming this points into ...
2
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1answer
1k views

How to fix incorrect SRID of the geometry column? [duplicate]

I've been told to use AddGeometryColumn to properly add a column with correct/preferred SRID. however I wonder if it's possible to fix/change the current column instead of adding a new? If there's no ...
2
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1answer
148 views

Calculating points in the USDA's Cropland Data Layer coordinate system

I need to integrate against the USDA's cropland data layer. They've got a demo and some API docs. The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537): ...
2
votes
2answers
494 views

Why is Spatialite delivering “Invalid SRID” error message

Qspatialite in QGIS 1.8 (and also Spatialite-gui) delivers an "Invalid SRID" error message when I try to load shapefiles with a SRID value of 3814 (Mississippi Transverse Mercatur). The SRID is ...
2
votes
1answer
13 views

Is it possible to get coordinate system name from SQL Server geometry type?

I need to get the name of the coordinate system of a geometry type field in SQL Server 2008 R2 (for example NAD_1983_UTM_Zone_14N or GCS_WGS_1984 or other). Is this possible?
2
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0answers
19 views

Problem with postgres/quantum converting long/lat to suitable projection/SRID [duplicate]

I'm sure it's a simple question but this is all very new to me and after a lot of internet searching my points are still in the sea! I have a set of UK postcode data that I have converted into ...
2
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1answer
251 views

Problem with writing the srsName into gml output in OpenLayers

I am trying to write out my geometry in gml format after it is drawn in OpenLayers. Actually it is working fine, I get the gml like this: <gml:Polygon> <gml:outerBoundaryIs> ...
2
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0answers
104 views

How to do Spatial Tools Projections between different projection types

I am working with the SQL Spatial Tools from http://sqlspatialtools.codeplex.com/ And a variety of data sets, primarily from LINZ and Google. These involve working with projections for 4326 (WGS84?) ...
1
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3answers
623 views

finding the definition of missing srid in postgis

I am converting a spatial Oracle database to POSTGIS, and one of the problems I encounter is that we use SRID in Oracle that do not exist in POSTGIS. I am talking about the following SRID: 90112 : ...
1
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1answer
304 views

PostGIS not converting GIS data into latitude/longitude values

I am running PostgreSQL and PostGIS. I am trying to do something mind-numbingly simple: determine the latitude and the longitude of a point. Unfortunately, PostGIS stubbornly refuses to transform the ...
1
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1answer
54 views

Reprojecting in postGIS from 900913 to 4326. Wrong coordinates

I'm working with postGIS 2.1 I have a table called 'xacementos' created with the srid: 900913. I took the points coordinates from google maps and I want to convert them to SRID:4326 to show the points ...
1
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1answer
354 views

How to transform ETRS to EPSG?

I have data in the ETRS 89 LAEA format (SRID: 3035). But I have problems to transform it. Example data: N2736 E4541 I want to transform it to EPSG WGS84 (SRID: 4326), to check the coordinates on ...
1
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1answer
276 views

Postgis | Problems Reprojecting a Point from UTM ED50 to GEOGRAPHIC ETRS89

I've got a POINTS PostGIS table in the 23030 (ED50 UTM 30N) SRID. I'm having a lot of problems trying to reproject those points from ED50 UTM coordinate system to ETRS89 Geographic (lat/long) ...
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1answer
141 views

PostGIS is rejecting an srid code for my projection. I've found a nearly identical projection w/ a legit srid. Will it work?

My projection is this: NAD 1983 StatePlane North Carolina FIPS 3200 Feet, which has a proj4 string that looks like this: +proj=lcc +lat_1=34.33333333333334 +lat_2=36.16666666666666 +lat_0=33.75 ...
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1answer
624 views

PostGIS - Geometry or Geography find points within distance in meters

I have a requirement where I need to store lat/long coordinates for locations all around the world. I then need to query for those locations that are within a specified distance (in meters) from ...
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1answer
911 views

SRID 4326 and geometry conversion

From this line: SELECT ST_AsEWKT(geom) FROM buildings LIMIT 1; I get this result: "SRID=4326;MULTIPOLYGON(((404269.308014269 4543087.6184561,...)))" I'm wondering if the coordinations are ...
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1answer
128 views

Get relative north aligned point 2163 (US Equal Area)

What I'm trying to do is create a grid where the y axis is north aligned. I have a origin Lat/Lon point which is the bottom left corner of the grid and each cell should be 100 by 100 meters. So I ...
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0answers
69 views

How to import multiple shapefiles each with different source projections to postgis

I have a couple thousand .zip files each with a .shp, .dbf, .shx, and .prj inside them that I want to load into postgis. The problem is, they have many different source projections (each defined in ...
1
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1answer
430 views

Inconsistent Spatialite Update Behavior; SRID not allowed?

I have two tables: crime and (police) stations. The latter has only 4 records with (name, lat, lng) fields. The former has over 500K records with two California Zone 2 (ft) coordinate columns named ...
0
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1answer
111 views

Why does Find_SRID return zero?

using SELECT Find_SRID('public', 'myTable', 'myColumn'); I get zero as the result, what does it mean? Regards,
0
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3answers
319 views

Override “ERROR: Operation on mixed SRID geometries” and force PostGIS to do the query

I'm trying to do an st_intersects query in postgis for two shapes (a point and buffer zone) which are of the same projected coordinate system. Unfortunately, one of the tables seems to have its ...