The process of converting the coordinates of a map or an image from one system to another, typically by shifting, rotating, scaling, skewing, or projecting them.

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Getting a Bounding Box in Latitude / Longitude using PostGIS shp2pgsql

Using the PostGIS shp2pgsql -s 4326 ... I generated the sql file and created my spatially enabled table. When executing my query: select box2d(ST_extent(the_geom)) from feature_data; I'm returned ...
11
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4answers
2k views

How to reproject spatial data using free libraries?

How can I use free libraries to transform spatial data? For example, I want to change the projection of a Shapefile within the code of my C# web application. How do I do that?
12
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3answers
7k views

How to move vectors to specified coordinates in QGIS?

I have a layer of vectors located around, say, (100, 100), and I want to move them to new coordinate like (1000, 1000). How should I do it? Preferably using QGIS.
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4answers
9k views

How to reproject base layers in OpenLayers?

The issue is: I have vector/topo/image tiled maps for some places in north america which were published as ArcGIS Server REST service. These maps (A) are based in EPSG26912 projection. Now I wanna ...
2
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1answer
666 views

Postgis: WGS84 Lat Lon Point to Gauss-Kruger 3

How do I convert a WGS84 lat lon point in postgis to Guass Kruger 3 (31467)? Somehow, I do not seem to get it right. I tried the usual way for converting projections: ...
3
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1answer
796 views

How to provide transform information to openlayers on Image layer

I would like to include an overlay raster layer into my OpenLayers map. I've pre-transformed the image into the correct projection (EPSG:900913) and saved as a png using the gdal_translate command: ...
4
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1answer
238 views

Access is Denied error on ProjectEx call

I need to be able to convert a lat/long coordinate into a point coordinate and am having trouble getting my code to work. I created a test app isloating the code that is giving me problems. I'm ...
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2answers
1k views

Online service to transform coordinates from WGS84 to NZTM and NZMG

Has anyone come across a free web service / REST API to transform coordinates? I'm particularly interested in transforming from WGS84 to: New Zealand Geodetic Datum 2000 (NZGD2000 / NZTM) and New ...
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3answers
2k views

Transform Data with Microsoft Spatial SQL

Is there a way to transform geographic data in SQL Server 2008 R2? Specifically, I want to take Lat/Long data and convert it to a State Plane coordinate system.
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2answers
525 views

How to detect MGRS/UTM zone?

I posted a similar question on StackOverflow, but I thought I'd check here as well. I am developing an open-source library for converting between coordinate systems, and I've run into a wall. I want ...
2
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3answers
1k views

Transforming shp files to projected coordinate system

I have some KML files, polylines. I will convert them in grass to shp. How can I transform coordinates to some projected coordinate system? I was never doing it, so please help me. I need to transform ...
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2answers
9k views

Converting projected geoTiff to WGS84 with GDAL and Python

Apologies if the following question is somewhat stupid, but I am only VERY new to this whole GIS thing. I am trying to convert some projected geoTiff images to WGS84 using gdal in python. I have ...
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1answer
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Converting Lambert Conformal Conic to WGS84 using Proj.4

I am attempting to transform data from Lambert Conformal Conic lat/long and I am having some issues with the results. The shapefile I am attemtping to transform can be found here: ...
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4answers
699 views

Given long, lat, x and y, how do I find the projection?

I am using an app called farsite that outputs shapefiles that show how forest fires will grow. I am getting output in coordinates as X and Y values rather than (lon,lat) and am looking for a ...
8
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3answers
10k views

Coordinate System Transformation in ArcMap

For the Data Frame Properties on a map in ArcMap, what is the difference between selecting a new coordinate system and using a Transformation?
8
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1answer
689 views

WGS72 to NAD83- how to find correct transformation

I am trying to get this raster file to convert from WGS72 to NAD83, but ArcMap10 doesn't appear to have the correct transformation listed. Where can I find this transformation, and/or how do I import ...
3
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3answers
673 views

FME - Possible to return a value from workspace?

I'm calling my workspace from the command line (either via Python or .NET to a system/os call). I'm parsing DWGs and pushing attributes to SQL Server in the workspace. Either the data validates in the ...
6
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2answers
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How should I use GDAL to perform a transformation?

Greetings, I am a student who wishes to use GDAL to transform a series of images from Lambert Conformal Conic (EPSG: 9802) to Google Earth's WGS 84 (EPSG: 4326) for a web mapping project. I know ...
4
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1answer
3k views

Convert Gauss-Kruger to UTM

How to covert Gauss-Kruger coordinates to UTM coordinates with GeoTools java library? As I have figured out the location (zone, country) is important. I need the calculation for Slovenia.
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1answer
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How can I transform GCS_North_American_1983 to GCS_WGS_1984?

I posted a thread today describing a shift in some of the NRC data (not all). Apparently, this shift has to do with conversion between Geographic coordinates, latitude and longitude and Transverse ...
14
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4answers
2k views

Rubber sheeting in GRASS or QGIS

We are in the process of getting our property boundaries corrected and a side effect of this is that we need to move any assets that have been drawn relative to the property boundaries, so they are ...
7
votes
3answers
888 views

Retrieve polygon smallest MBR

I have a postgis table containing polygons. I want to transform my polygons to 4 points polygons : retrieve the smallest MBR. Here comes an illustration of what I want : My original polygon is ...
7
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1answer
2k 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 ...
3
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1answer
714 views

Ordnance Survey data to WGS-84

Recently I have reprojected Ordnance Survey data from British National Grid (ORD SURV GB) to WGS-84 using ArcGIS 9.2. After re-projecting I have found some shift in the data. Can any body guide me ...
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2answers
663 views

Why are the coordinates transformed with proj.4 off compared to http://valdemar.kms.dk/trf/?

I am trying to transform from epsg:4326 (wgs84) to epsg:25832 (utm ETRS89) using Proj.4. I am comparing the results with results from http://valdemar.kms.dk/trf/ . it seems like the results ...
4
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1answer
302 views

Is a WMS map always a constant scale?

If I get a map back from a WMS server is the scale always constant over them map regardless of the reference system? So if I have a map which is 100 pixels wide, will the point at 50 pixels always ...
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2answers
950 views

Which ESRI defined geographic transformation do I need to use to convert my “ NAD83 Northern Virginia” data into WGS 1984 Web Mercator?

My title pretty much tells it all.. I have a number of datasets in which I want to batch project from NAD83 Northern Virginia Datum into the correct Web Mercator projection.. When I do a straight ...
11
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6answers
646 views

Where can I find GIS data to test GIS coordinate operations?

I am trying to find some data that can be used to test GIS coordinate operations from one CRS to another CRS. So far all I have found is the Gold Data set and also various example points in the EPSG ...
5
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5answers
7k views

How to convert coordinates from Gauss-Krueger to Longitude/Latitude?

I'm a newbie in the GIS world so please advise me :) In my .NET/C# project I need to show some shapes/points on the Bing Map. The problem is I have the Gauss-Krueger coordinates and need to convert ...
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2answers
478 views

CORS - HARN transformations - what is the most accurate method

This may not be an issue for many GIS-ers but has anyone else had experiences transforming from modern NAD83 (CORS) to HARN coordinates and vice versa? I realize the discrepancy might be something ...
2
votes
1answer
444 views

How to convert SHP/POSTGIS data into x, y, z, “cost” data?

Is there a way to convert a line layer (shp or PostGIS) data into (x, y , z, cost) i.e. (From_node, To_node, optional_Elevation, Cost/Weight) ?