Tagged Questions

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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0
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0answers
34 views

QGIS layer only displays when I uncheck on-the-fly transformation

I have a layer that covers the stats of Indiana that has the following Layer SRS: +proj=utm +zone=16 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs It will not display unless I uncheck the ...
1
vote
1answer
96 views

QGIS with CH1903/LV03 and WGS84 layers

I have a few CH1903/LV03 layers (lake, river and the country border of Switzerland) and a layer in WGS84 (two points of two cities, Vaduz and Bregenz). On-the-fly-transformation is activated but ...
2
votes
1answer
82 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
votes
2answers
118 views

Problems with transformations in ArcMap

I have files projected in British National Grid. After I have transformed them into WGS_1984. I noticed that if I were to transform them back to BNG the original would not match the new. Is there a ...
2
votes
1answer
112 views

How can I transform Real-time Local position system coordinates into GPS/WGS84?

I have a local coordinate system built with Ubisense sensors and tags (it is a real-time locating system used to automatically identify and track the location of objects or people). The local ...
0
votes
1answer
652 views

From GCS_WGS_1984 to UTM WGS 84 zone 33N

I was doing my project and i had to transform shapefile from bessel to gcs_wgs_1984. that went fine. Now I have to put it again to projected coordinate system. Please could someone help me transform ...
1
vote
1answer
104 views

FME: how to extract the coordinate of the North West corner

In an FME translation from a polygon geodatabase feature class to a DGN I am trying to place a label in the top left corner of a box. I have tried using CoordinateExtractor to find the coordinates of ...
1
vote
1answer
108 views

Buffer Zip Region Polygon with GeoTools

What I want to achieve is to buffer a zip region geometry with a distance in meters and than get the coordinates of the new (expanded) polygon. The original geometry polygon is parsed from a kml file. ...
2
votes
2answers
221 views

Vector affine transformation in QGIS2

In QGIS 1.8, I can transform my point layer with the plugin "Affine transformation". So, this plugin don't exist in QGIS 2.0. Do you know a method to simply translate (i.e : X -> X+30000) in QGIS 2 ? ...
1
vote
1answer
856 views

Trasformation from ECEF to ENU

I am trying to transform a local vector rECEF from ECEF coordinate system to ENU coordinate system (rENU) where ECEF = earth-centered earth-fixed coordinate system ENU = East, North, Up coordinates, ...
0
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2answers
47 views

transform bound for google map

i have wms layer with coming geoserver and it's bounds is bounds = new OpenLayers.Bounds(417138.6205791628, 4243634.852681775, 486211.1950145211, 4331542.555877601).transform(WGS84, ...
0
votes
1answer
617 views

Convert GeoJSON form EPSG 3857 to 4326 with JavaScript [duplicate]

Given a GeoJSON in EPSG3857: { "type": "Feature", "properties": {}, "geometry": { "type": "LineString", "coordinates": [ [ -13720479.997764934, 5688254.733325758 ...
2
votes
1answer
209 views

Why are xy coordinates displayed in my WGS84 project instead of lat/lon?

I have a project in QGIS comprised of shapefiles and raster maps. The origin CRSs are mostly on ETRS89 / Portugal TM06. I am trying to convert the project to WGS84 to have lat/lon instead of metric ...
4
votes
2answers
170 views

Why Different 2D Coordinate Transformation Methods Exist

It is a homework question but I couldn't find a satisfactory answer by googling. There are 4 different transformation approaches I'm asked for: - Conformal, - Affine, - 2D Projective, - 2D Polynomial ...
2
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0answers
64 views

Using ST_Affine() and trans_param() functions on vector layer

After reading this post How to georeference a vector layer with control points? I decided to give it a try to move/rotation/scale a polygon using Postgis. I have two polygons, polygon_from and ...
2
votes
0answers
91 views

How to locate a house on the 3D Map correctly?

I've done my 3D map generation in WebGL/THREE.JS project and have an issue with the building locations. I have the data about building position ( its polygon ) from DB server, but first of all I want ...
4
votes
1answer
187 views

GDALWARP and OGR2OGR / CS2CS not agreeing on transformation

I am trying to transform some data (both raster and vector) from WGS84 to a Croatian Coordinate system defined by: +proj=tmerc +lat_0=0 +lon_0=15 +k=0.9999 +x_0=5500000 +y_0=0 +ellps=bessel ...
1
vote
1answer
133 views

How to get WGS84 lat lon bounds from a VRT file

I have vrt files generated using gdalbuildvrt that reference GeoTiffs referenced using the NZTM coordinate system. Is there an easy way to determine the bounds as WGS84 latitude longitude ...
3
votes
4answers
691 views

Issues using geographic and projected coordinate systems QGIS 2.0

I am having issues with QGIS 2.0.1 working between local projected coordinate systems (such as OSGB36, NAD83) and Geographic systems (such as WGS84). The stock answer I have been provided is 'load ...
1
vote
1answer
49 views

Transform an Irish grid reference (29903) into UK grid reference (27700) on insert

I have an insert script to input several hundred points, however some of the points use the Irish Grid Reference system. I have separated these out however was unsure how to convert or transform? ...
1
vote
2answers
64 views

How to figure out the SRID of a point by comparing it to another point with known SRID?

I have a set of store locations defined in the coordinate system of Bottincarto, which I need to display on Google Maps iOS. Here is an example of coordinates for Notre-Dame-de-Paris: 600926 ...
0
votes
2answers
161 views

Convert the_geom to text and then transform

I have this query that returns the_geom as text. However how could I also apply a transform to the same query. I can do this separately with the second example. Though I would like to do this to all ...
3
votes
0answers
166 views

Can GDAL Perform Vertical Transformations?

Can GDAL perform vertical transformations? If the answer is yes, please indicate which amongst these listed pages can explain how exactly to accomplish vertical transformations? If there is some ...
2
votes
0answers
50 views

How do you compute vertical transformations in QGIS?

How do you compute vertical transformations in QGIS? Ideally, the procedure / plugin will allow the loading of sundry geoid models.
6
votes
3answers
519 views

How does ArcGIS determine which transformation to use when projecting on the fly?

How does ArcGIS determine which transformation to use when projecting on the fly? Where this would come in would be going from NAD 83 to WGS 84. Multiple transformations could be considered so how is ...
11
votes
2answers
402 views

Huge differences between results for 7-param datum transform

I'm trying to transform a WGS84 lat/lon point 11d42'32.10629" E 5d12'56.75371" S in three different software packages (Proj4, GeoTrans and Leica GeoOffice) but I receive very big differences ...
0
votes
1answer
73 views

Transform from PSA56 to NAD83

I need to transform some data from PSA56 to NAD83. It doesn't have to be that rigorous as it's purely for a context map. I'm guessing I will need to go to WGS84 and then to NAD83. If anyone has any ...
2
votes
1answer
193 views

QGIS Georeferencer, unexpected transformation, and GCP placement

Im trying to get the sample map which i believe to be EPSG:3112 into QGIS and geo referenced. In my screenshot, on the right is the raster in georeferencer with the points i have added. On the left is ...
2
votes
1answer
3k views

Transforming from SRID 900913 to 4326 with PostGis

I have two Postgres tables with different SRIDs, 4326, and 900913. I want to convert the latter to 4236. I first changed the SRID using: Select UpdateGeometrySRID('table', 'geomcolumn', 4326). I ...
0
votes
0answers
96 views

Transforming WFS Projection

I am trying to overlay features from a WFS using OpenLayers, my geometries in database are in EPSG:27700 and my map's projection is EPSG:3857. My mapfile returns data in EPSG:27700. Is there any way ...
2
votes
0answers
344 views

GDAL: Geotransform - rotated rasters (and ArcGis)

I am working on a GDAL driver for a proprietary grid-format. In some cases, the grids are rotated in order to get smaller file sizes. In my GDAL geotransform array, I do the following (showing a ...
0
votes
1answer
248 views

How to transform/convert Coordinate Reference System with Proj4 and php

Basically my question is: Can I combine the functions of proj4 with php in my server? For example, I would like to know if it is possible get data in WGS84 and transform in ETRS89. I need to get ...
0
votes
1answer
53 views

USGS FLT Hdr file interpretation

I have a legacy program that attempts to read USGS 1/3 arcsec data. When I compare results to GDAL, I find that the lat/lon to pixel conversion is off by 1 line. The reason (I think) is because the ...
3
votes
2answers
110 views

Determining closest representation of polygon as collection of points+radii

Have a bit of a tough question, which I realize there may not be an easy solution to. Figured what better place to ask. I'm attempting to transform a polygon into a series of arbitrary points with ...
1
vote
1answer
106 views

ArcGis: Rotated grids and cell size

I am using ArcObjects, namely RasterGeometryProc, to apply rotation on grids. The transformation works fine. However, when looking at the grids properties in ArcGis, the cell sizes has changed. ...
2
votes
1answer
452 views

Exporting geographic coordinates in QGis as projected (flat) coordinates

I've created some polygons with Google Earth which I'd like to convert to my flat map's coordinate system. I've loaded a few shapefiles into QGis of a county's roads, parcels, etc. The coordinate ...
3
votes
1answer
399 views

When trying to convert lon/lat (curved) coordinates to projected (flat) coordinates with ruby, the second (y axis) projected coords are inaccurate

So I have created a polygon using Google Earth pro. I've exported it into a kml file, which I can then parse using ruby's XML/HTTP-parsing Nokogiri gem into an array of WKT points (LinearRing) thats ...
0
votes
1answer
501 views

Geographic Transformations using ArcPy vs. Coordinate Systems used by ArcGis online basemaps

I have 3 shape files with undefined projection, but I know which one it was used (Lisboa_Hayford_Gauss_IPCC). I need to 1st Define Projection. It works. I need to transform it from WGS_1984, so I've ...
1
vote
2answers
246 views

PCS and GCS Transformation

Trying to trasnform GCS_Bessel_1841 PCS_Trasnverse Mercator (central meridian 18) to WGS1984 using "Project tool" in ArcGIS 9.3. I tried to do it in several different ways, every time from the ...
0
votes
1answer
675 views

From Bessel 1841 to WGS 1984

I am having problem with projecting my counties which are in GSC_1841/Hermannskoegel to WGS_1984 in ArcGIS 9.3. I tried the basic "project" with importing the existing coordinate system but that's ...
1
vote
2answers
346 views

Convert 3D WKT to 2D Shapely Geometry

I have the WKT of many linestrings which contains three dimensions, however my script only requires a two dimensional linestring and I therefore want to discard the third dimension. My current code, ...
1
vote
1answer
4k views

How can I convert/transform coordinates from ETRS89 to WGS84 Utm 36N in QGis

I am a student and just getting to know qgis. At the momment I have to combine data which had been measured in ETRS89 with data in WGS84 UTM 36N. I created several vektorlayers for the data in ETRS89. ...
3
votes
2answers
243 views

GeometryServer > Project with Datum Transformation

I am facing the problem that when i use the extent in the url and i go from Amersfoort(WKID 4289) to WGS84(WKID 4326) that without the tranformation the point from longitude and latitude is placed ...
3
votes
1answer
296 views

Programmatically manipulate GPX data

I need to do the following in Python open OSM & GPX files (I have packages for this) transform points from GPX (like stick a track to roads) calculate the results (distances, cumulative ...
4
votes
3answers
523 views

generate spatial geom from lat lon points for map in PostGIS

I am interested in a PostGIS implementation of the R-based soulution from a previous question, How can I convert data in the form of lat, lon, value into a raster file using R? Currently, I am hoping ...
1
vote
1answer
758 views

Transform regular lat/lon to rotated lat/lon

I am currently working with climate data projected in a rotated lat/lon grid and came across this excellent 'cookbook' by mkadunc on how to manually transform rotated lat/lon to regular lat/lon: ...
4
votes
1answer
391 views

Experiencing transformation anomalies when performing a Save As to convert coordinates between NAD83-Z14 and NAD27-Z13

Good morning all: I have recently discovered QGIS and have been hoping to find a solution for converting bacthes of xy coordinates between two projection systems for our mapping system. I have known ...
1
vote
1answer
125 views

Geographic Transformation

I have an Image with the following metadata: Projection Information : Projection Zone : 0 Spheroid Name : Modified Everest Georeferenced to : RSO Map Information : Upper Left ...
0
votes
1answer
294 views

geotools / jts crs transformation result not at correct position

I copied the example from geotools, which shows how to transform a shapefile into a different projection. (http://docs.geotools.org/latest/userguide/tutorial/geometry/geometrycrs.html) But when ...
5
votes
1answer
201 views

How much error in a transformation?

I've been working in GIS for about a year and have a functional grasp of Projections and Transformations from within ArcGIS (10.0). Geosoft Oasis is another program we use. In working with our data ...