The coordinate system known as World Geodetic System 1984 (EPSG:4636)

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8
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2answers
6k 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 ...
-1
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0answers
33 views

How to convert from Cartesian (X,Y) to WGS84 Lat Lon [on hold]

Given that I know the origin and the x and y cartesian coordinates. How do I find the corresponding lat lon? lat = lat_origin + ((y / 1000.0) / (111.319 * rad_to_deg)); lon = lon_origin + ((x / ...
3
votes
1answer
66 views

Find intercept WGS84 coordinates between two segments defined by (Lat1-Long1 and Lat2-Long2) and (Lat3-Long3 and Lat4-Long4)

I need to determine the WGS84 coordinates for a point that is defined by the interception of two segments represented by two sets of WGS84 coordinates each (lat1-long1, lat2-long2) and (lat3-long3, ...
2
votes
1answer
303 views

How to convert (geodetic pose + cartesian offset) to geodetic position

I am in search of an algorithm to solve the first/direct geodetic problem precisely in 3D. The input is: a geodetic (not geocentric) position (WGS84, height is above the WGS84 reference ellipsoid) ...
2
votes
1answer
34 views

Why this two datasets don't match?

I have a postGIS database in SRS 4326 (WGS84) with several Europe layers working well, but when I load a shapefile projected to the same SRS with QGIS, the layers don't match. To explain it better ...
2
votes
1answer
38 views

Geographic Transformations in Alaska Between NAD83 and WGS84

I have done a ton of research on the most accurate transformation to use in mainland Alaska to convert between the NAD83 and WGS84 datums, but I just can't seem to find a definitive answer. ArcMap ...
2
votes
1answer
50 views

How do I convert Eastings and Northings projection to WSG84 in geopandas?

I'm very new to projections and struggling to convert a map dataset from OSGB36 (Eastings and Northings) to WGS84 (lat/longs). I've used geopandas to import a shapefile. Now I want to export it as ...
2
votes
0answers
354 views

Projecting a Raster from WGS84 to planar Equal Area to Calculate Area: How to Select the Cell Size?

I have a broad question on how to calculate the 'correct' cell size for a raster when analyzing an area not at the equator. My goal is to project a land cover raster provided in GCS WGS84 to an equal ...
1
vote
2answers
59 views

How do you convert SRTM HGT elevations from WGS84 into meters above sea level?

I am building a JavaScript script that reads binary HGT files - as generated by the SRTM - and converts the data into bitmaps viewable in your browser. You can try out the script and view the source ...
4
votes
0answers
51 views

GeoJSON shape distorted on Leaflet.js spherical mercator WMS map [closed]

I have a map with a simple WMS layer in spherical mercator projection (rendered by a OSM-Mapnik-TileCache server stack, everything is in EPSG:900913 / EPSG:3857). First: I can't understand why, if ...
1
vote
1answer
30 views

OpenLayers Projection and Datum Question

I had a conversation with a co worker that was asking about an OL map I am developing. She asked me what the 'projection' was and I said EPSG:4326. She didn't know what that means, so I said it's ...
1
vote
1answer
79 views

Problem with import CSV files to QGIS 2.0.1

I have a problem with import CSV files to QGIS 2.0.1. I have a file with WGS84 coordinates it looks that: Nr;Longitude;Latitude 1;18,06,23.66;54,83,12.50 2;18,08,81.30;54,73,09.30 ...
2
votes
1answer
241 views

Lambert93 to WGS84, IGN algorithms, longitude problem

I'm looking for a Java-based solution to convert coordinates from Lambert93 to WGS84. I found this, "lambert-java", which is an implementation of the algorithms (PDF) published by IGN (French ...
5
votes
2answers
322 views

Stereographic projection of WGS84 ellipsoid on a plane[python]

I would like to ask you for help in following task. What I need to do is to derive local x,y coordinates from latitude, longitude, applying stereographic projection of WGS84 ellipsoid on a plane, ...
1
vote
1answer
48 views

Why do MGI and WGS 84 data not line up in ArcGIS for Desktop?

When i reproject raster from MGI 6 zone to the WGS84 it makes a mistake (it is moved for 380 m )See example below: I know that the problem is in MGI 6 projection (it is not accurate),but I do not ...
8
votes
4answers
7k views

How do I calculate the bounding box for given a distance and latitude/longitude

Hi need to be able to calculate a bounding box or circle for a Given WGS84 latitude and WGS84 longitude, and distance but have no Idea where to start! The distance from the start lat Lon would be 10KM ...
2
votes
0answers
21 views

Re-projecting WGS84 to OSGB in SAGAGIS

I took some points with a GPS, and I'm trying to convert from GCS to OSGB 1936 British National Grid in SAGAGIS. I'm working with a shapefile. To reproject the vector layer to the OSGB projection I ...
2
votes
2answers
82 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 ...
0
votes
0answers
43 views

How to determine the Geoid model used by GPS receiver?

I have the following NMEA output by Holux M-241 GPS receiver: $GPGGA,144014.000,2227.0987,N,11410.1382,E,2,6,1.67,32.6,M,-1.3,M,0000,0000*7B I know that WGS84 height is higher than geoid height 1.3 ...
3
votes
1answer
130 views

How to convert a CSV from DMS to WGS84 in QGIS?

I would like to automatically convert from a Degree - minute - second system to WGS84 EPSG:32632. I have a CSV with these kind of values: LATITUDINE LONGITUDINE 46°01’24,7” 11°13’47,5” 45°42’07,5” ...
16
votes
6answers
8k views

Map projection in OpenLayers

I want to overlay some data whose projection is WGS-84 on Google map layer in OpenLayers. But I just can't make them in the right place. I did as follows: map = new OpenLayers.Map('map', { ...
1
vote
1answer
154 views

How to Extract Data from U.S. National Landcover Dataset (NLCD) dataset?

I am working with U.S. National Landcover Dataset (NLCD) to classify habitat type at more than 150 sites across the northeast U.S. The dataset is very large (15GB) so I cannot upload it here, but it ...
3
votes
1answer
345 views

How to reproject MODIS Swath data to WGS84

Im new to GIS and now working with MODIS04L2 Aerosol Optical Thickness image. I need to reproject the image to other coordinate system such as WGS84 for later work but now Im stuck with it. I have try ...
0
votes
0answers
46 views

issue with QGIS Scale Level

I have different layers of shape files. I have imported all shape files into PostGIS. Now i want to show 3 layers Country, State & District with different scale/zoom level I tried to set scale ...
2
votes
1answer
28 views

WGS84 CRS without elipsoid

What's the difference between using CRS defined as +proj=longlat +datum=WGS84 +no_defs and a CRS defined as +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs Will using one or the other pse any ...
1
vote
1answer
114 views

Convert measurement geometry from ground reference frame to satellite reference frame

I need to convert solar_zenith_angle, solar_azimuth_angle, platform_zenith_angle, and platform_azimuth_angle from a reference frame at the WGS84 surface to a reference frame at the satellite observer, ...
1
vote
2answers
119 views

On the fly transformation From WGS84 to NAD27 with proj4 code

I want to use this proj4 code: +proj=utm +zone=19 +ellps=WGS84 +toclrk66=-3,142,183,0,0,0,0 +units=m +no_defs or this one +proj=utm +zone=19 +ellps=WGS84 +tonad27=-3,142,183,0,0,0,0 +units=m +no_defs ...
1
vote
2answers
46 views

Why does my gpx layer go to the wrong spot even if they have the same CRS?

Help! I am a QGIS beginner with a big problem! I am trying to load a gpx file from Garmin into my map. The project CRS is WGS 84, and the incoming data is in CRS WGS 84. When I look at the bottom of ...
3
votes
4answers
429 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 ...
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vote
3answers
716 views

Searching for c# code to convert from UTM to WGS1984 (and back)

I'm looking for code in c# that converts coordinates from UTM to WGS1984 (and preferably backwards as well). I need to convert coordinates from only one zone (36N). I've found this and this, but they ...
3
votes
1answer
55 views

How to get projected centroids in QGIS?

I am trying to get a centroid for several polygons on a global scale, in a way that it would correctly represent the common centre of all the polygons, taking Earth's curvature into account. The ...
10
votes
1answer
355 views

How to find ring of coverage of GPS Satellite on WGS-84 ellipsoid?

Given the following: Time, t The set of IS-200 Ephemeris data, E, of a GPS Satellite corresponding to time t The ECEF position of the GPS satellite, P=(x,y,z), derived from the time and ephemeris, ...
2
votes
1answer
153 views

How to convert WGS84 to UTM when the study area covers two zones: UTM 51N and 52N

I want to use ArcMap to convert the WGS84 to UTM. But the study area covers two zones: UTM 51N and 52N. Which zone should I choose to output the result? 
2
votes
2answers
179 views

Stereo 70 where is it?

I have ortho photos of Romania in Stereo 70 and GPS data in WGS84 of the same country : I want to associate the two series of data. At the moment, I can't find Stereo 70 in the list of CRS : does it ...
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0answers
92 views

GeoTools: SimpleFeatureCollection to KML error CoordinateReferenceSystem

I want to export a SimpleFeatureCollection (Read from a MySQL DB) to a KML file, here is my code used to read the infos into the console: private void featureCollectionToKML(SimpleFeatureCollection ...
3
votes
1answer
349 views

How to convert to Australian Height Datum from Google Earth elevation?

I am trying to figure out how to convert from Google Earth elevation to Australian Height Datum (AHD). Google Earth's elevation / altitude is based on The vertical component (altitude) is measured ...
3
votes
1answer
99 views

Problem with projection in layer

I'm having problems with visualizing a layer which is in EPSG:4326 Apparently the geometry looks perfect, but I don't know why, it's not in real coordinates. I have projected it to 4326 with QGIS, ...
10
votes
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 ...
2
votes
1answer
118 views

What is the range of numbers for coordinates in geographical coordinate systems

Up to now I thought the range of values in the geographic coordinate systems was: Northing : between -90 to +90 Easting : between -180 to +180 I have set the coordinate system of my dataframe in ...
4
votes
4answers
793 views

What is the projection of WGS84 in GIS software?

WGS84 is a reference ellipsoid that determines coordinates of every point on Earth using latitude, longitude and height about the its surface. This ellipsoid is often used as a base to make maps. ...
3
votes
1answer
83 views

Rhombus shaped pixels when viewing an image referenced in WGS84

Following the Question What is the projection of WGS84 in GIS software?, in the comments section of the answer http://gis.stackexchange.com/a/73578/5256, Jake very well explains that Because the ...
0
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0answers
143 views

QGIS 1.8 problem with rendering polygons in WGS84 on Ubuntu 12.04

I'm using QGIS 1.8 on Ubuntu 12.04. If I add a polygon layer in SHP format and WGS84 projection and start to zoom in, from a scale of 1:200.000 aprox. polygons on the edges are not drawn anymore and ...
2
votes
1answer
420 views

Canvas Units to Degrees, Minutes, Seconds

I am using the WGS 84/UTM coordinate sysytem. When I go to > Project Properties / General / Canvas Units to Degrees, Minutes, Seconds my coordinates are wrong. I am using QGIS 2.0.1
5
votes
3answers
124 views

What is the precise distance from equator to pole according to WGS84?

For calculating areas of polygons by means of projecting to a cylindrical equal area projection I came across the following discrepancy: I ended up with a different distance, off by more than 5km, ...
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vote
3answers
1k views

How to convert Lat & Long from Onemap.sg to Google Maps

I have a set of address for Singapore, I would like to take the Lat & Long from onemap.sg (SYV21: X, Y / Easting, Northing) and then store it in my databse , convert into (WGS84: Longitude, ...
3
votes
1answer
241 views

Are these two OGC WKT projections the same? And if so, why are their reference strings different?

So here is the .prj text of a federal shapefile dataset of all public airports in its native OGC WKT format: ...
2
votes
0answers
90 views

Height of the geoid in ECEF coordinates

I know that the relationship of geoid height N and ellipsoid height h to orthometric height H is defined by H = h - N, but what if I have some position in Earth-Centered-Earth-Fixed (ECEF) ...
2
votes
1answer
409 views

How to make world file in WGS84 out of OpenLayer's Google Earth layers?

I would like to make world file out of OpenLayer's Google Earth. The problem is, that Google Earth layers in Qgis are shown EPSG:3857, but I need just standard WGS84 (ESPG:4326). When I try to set ...
2
votes
1answer
996 views

Trying to convert coordinates from WGS84 Web Mercator Auxiliary Sphere to WGS84

I've been struggling with this for way too long now. I've got some data that was georeferenced in the WGS84 Web Mercator Auxiliary Sphere that should have been done just in WGS84. The Auxiliary ...
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vote
1answer
279 views

How do you convert from GPS data in WGS84 to a GIS built in NAD27 in ArcGIS?

I have GPS data that has been recorded in Datum WGS84. The client has a GIS built in Datum NAD27. Having looked into the conversions online I would like to know how to do this rigorously with ...