A reference framework consisting of a set of points, lines, and/or surfaces, and a set of rules, used to define the positions of points in space in either two or three dimensions.

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3
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1answer
70 views

How can I carry out a reliable coordinate transformation for point data?

I have ArcGIS 10.0 with ArcGIS Server (AGS) 10.0. Due to a known bug in the AGS geometry service we cannot carry out coordinate transformations with AGS 10.0. Our Internet client therefore does not ...
2
votes
1answer
98 views

How do I set the projection and coordinate system for a TIFF file?

I have a topographic map of California (obtained from CAL-Atlas) as a TIFF file. I tried importing it into QGis, but it displays the map using a pixel based coordinate system rather than ...
1
vote
1answer
184 views

How to identify township range and section from longitude and latitude

I have several hundred coordinates in an Excel file. I would like to identify the township range and section they are located--what is the easiest way to do this? I have you QGIS and basic GIS skills ...
0
votes
0answers
27 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 ...
4
votes
1answer
139 views

What projection system for the entire world should I use to calculate distances ArcGis?

I've got two point shapefiles (A and B) that represent features all over the world, and I'm using Near (Analysis Tools-Proximity). I'm trying to calculate the distances between the points in layer A ...
1
vote
1answer
141 views

In Ogr2OGR: what is SRS?

I am trying to understand this command: ogr2ogr -f "MapInfo File" original.tab wgs84.shp -s_srs EPSG:27700 -t_srs EPSG:4326 I don't understand the s_srs and t_srs paramaters. The help file says ...
1
vote
1answer
131 views

DotSpatial.Projections Vs. ProjNET4GeoAPI

DEAR PEOPLE FROM THE FUTURE: Here's what we've figured out so far… I have been facing the issue of transform coordinates from a custom spatial reference to a well known spatial reference (let's say ...
1
vote
0answers
87 views

Intersection between a ray from lat, lon, alt, with pan, tilt and earth's surface

I have a problem that consists of finding the intersection point between a ray from a given lat, lon, alt, that is looking to a given pan and tilt angles and the earth's surface. I need the lat, lon ...
1
vote
1answer
79 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 ...
1
vote
1answer
93 views

How can I use the proj string in java code?

I want to do projection from UTM/oblique mercator CRS to WGS84. And I know the solution to use a proj.4 string in commandline like+proj=omerc +lat_0=51.4 +lonc=7 +alpha=-10 +k=1 +x_0=0 +y_0=0 +gamma=0 ...
0
votes
1answer
443 views

Convert long/lat to indian grid system

how to convert lat/long coordinates to Indian Grid system? I've googled for a couple of days but didnt find the exact algorithm for this. and i got a link Indian Grid System. but i didnt get a picture ...
0
votes
1answer
71 views

Changing CRS for basemap from OpenLayers plugin

Relatively new to QGIS here and I haven't been able to find this question answered yet. I'm working on plotting data from NYC (Queens, specifically) and I would like to overlay my heatmap on a basemap ...
7
votes
1answer
227 views

Can I just swap out a .prj file to reproject a shape file?

I'm an experienced software developer -- but a GIS noob. I have a shape file that I am trying to turn into a SVG map with Kartograph. When I try to run Kartograph I get this error: ERROR 6: No ...
0
votes
0answers
42 views

recalculate latitude and longitude from a pixel in a cropped map

i want to recalculate a geographic coordinate from a pixel in a map. For this i have the size and the coordinates from the map to convert a coordinate to a pixel is use the algorithm, you find at ...
2
votes
1answer
44 views

App using latitude and longitude, should decimal degrees be a separate selection from metric?

So silly question to some I suspect. I am coding a mobile app that displays coordinates in parts of the interface. We currently have an option to toggle between Imperial and Metric. But I am unsure if ...
1
vote
3answers
117 views

How ensure data put into PostGIS gets proper CRS attached?

I recently had an intractable problem that we finally traced back to the fact that some points in a PostGIS table had a CRS associated with them and others did not. This resulted in some points being ...
3
votes
3answers
166 views

How to read coordinates with variable Gauß-Krüger zone (meridian) in QGIS?

Is there a sensible way to visualize coordinates like this as point layer in QGIS? X values starting with 2 are EPSG 31466, 3 is 31467 and 4 is 31468. I didn't try, but i think the same problem will ...
2
votes
1answer
469 views

What is the process to calculate Helmert parameters?

I have some double points (the same points in 2 different datums). I'd like to calculate the Helmert parameters but I don't understand how. NOTE: I don't need software. I need an algorithm in order ...
1
vote
1answer
256 views

Leaflet setView with non lat/long CRS

Is it possible to use setView when using an alternative CRS? var map = L.map('map',{crs: L.CRS.EPSG26915}).setView([4970081,477018], 13); // Returns: Uncaught TypeError: Cannot call method ...
0
votes
1answer
56 views

What is the CRS for France

Has anyone any idea what the CRS is for France? I am new to QGIS (moving over from using Arcgis) and trying to find out basics. I have found a huge list beginning NTF (Paris) but wonder which one to ...
0
votes
1answer
44 views

Unable to expand projected co-ordinate system folder in ArcMap 10.1

On trying to re-project any raster from GCS to any PCS, in the "Spatial Reference Properties" window, my "Projected Co-ordinate Systems" folder is not expanding. Where as the GSC folder is expanding. ...
2
votes
3answers
223 views

What are the differences between 81989 and 27700 CRS for the British National Grid?

We are using applying Oracle Spatial to run point in polygon queries in Great Britain using Ordnance Survey MasterMap and point data. MasterMap is on British National Grid (BNG) and has the ...
8
votes
1answer
197 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 ...
1
vote
1answer
54 views

How to derive GetFeature URL from capabilities document?

Given this capabilities definition how can I compose a GetFeature request that downloads the actual geodata? I came up with the following URL refering to WFS 2.0.0: ...
2
votes
2answers
101 views

How do I set a CRS when it isn't listed in QGIS? (Mac, not PC)

I want to work with a shapefile that is in a Coordinate System that I can't locate in QGIS for Mac. When I load this shapefile data, it shows up fine, on-the-fly has generated the CRS data most likely ...
2
votes
1answer
132 views

Open Layers and OSGB 1936 (CRS 27700)

I've been working with loads of shapefiles projected according to OSGB 1936 (CRS 27700). THe project CRS is set to 27700 and "On the fly reprojection" to 27700 is set (I keep this as a default as I ...
1
vote
1answer
31 views

Capturing GPS coordinates on the ground in Boliva?

Assuming no cellular or internet connection, what is the best way to capture GPS coordinates on the ground in Boliva? Preferably a free approach. For example, are their any android apps that can do ...
0
votes
1answer
73 views

How to reproject Network Dataset from GCS_WGS_1984 to Web Mercator?

I need to know how to change the coordinate system of my feature dataset with its network dataset from GCS_WGS_1984 to Web Mercator. Once I know how to do this, I would like to make a tool in Python ...
4
votes
2answers
86 views

Why is it not advisable to perform spatial analysis on layers with source datasets having same datum but different projections?

I have read that it is not advisable to perform spatial analysis on two layers with source datasets having the same datum but different projections loaded in ArcMap. Since the second layer should ...
1
vote
1answer
362 views

Pseudo-Mercator projection with Decimal Degrees?

Hope this isn't a duplicate, did some searching but none seemed quite the same. Projection I want: WGS84/Pseudo-mercator. Selected. Looks Great. Canvas units I want: Decimal Degress. Selected. ...
1
vote
1answer
85 views

How to reproject from Clarke_1880_RGS_Lambert_Conformal_Conic to ETRS_1989_LAEA?

I am unable to reproject Marseille shapefiles from Clarke 1880 RGS_Lambert_Conformal_Conic to ETRS_1989_LAEA. I know that Clarke is a geographic coordinate system and it has no datum. I have tried ...
1
vote
1answer
614 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, ...
4
votes
2answers
955 views

What formula is used for distance between 2 points in Google Maps?

What formula is used by Google Maps for calculating the shortest distance between 2 points (having their Lat, Lng coordinates)? Is it purely based on Haversine? Or is it something different? Is there ...
2
votes
3answers
351 views

How to calculate Polyline length in kilometres without changing projection from WGS84 (using ArcObjects)?

I have Road (polyline) feature class and I wish to find those roads whose length are greater than 500 kilometre. The feature class projection is in GCS_WGS_1984 and I do not want to change the ...
1
vote
2answers
65 views

Create Geographic Reference for X,Y Coordinates [closed]

I have a set of x,y data that do not have any sort of geographic reference. I have lat/longs (WGS 84) for a small set of those points. How can I calculate lat/long for the remaining points so I can ...
6
votes
1answer
155 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 ...
3
votes
2answers
124 views

Convert data to another Coordinate Reference System

Assuming I've a point like this : POINT (751318 9760879) This point is in EPSG:27700 coordinate reference system. How do I convert the point to display in a map with EPSG3857 coordinate ...
0
votes
2answers
80 views

How to choose spatial reference for GPS data?

We received GPs data from the vendor. I want using ArcGIS software to create XY event table and create a point feature class. What the spatial reference would be for the GPs data? Is it something I ...
-1
votes
1answer
201 views

How to project geographic coordinates to cartesian with the least possible error? [closed]

I need to convert geographic coordinates (in decimal degrees) to cartesian with the least possible error? I searched a lot on the internet but it seems that the conversion is not exact. Could you ...
1
vote
0answers
60 views

How does Arbitrary Coordinate System in QGIS work?

I have got the drill hole data, which needs to be geo-referenced based on non-earth coordinates system (with no datum, ellipsoid information defining through Custom CRS). Could any one explained me ...
3
votes
2answers
221 views

QGIS DXF file projection match

I need to use this file on a map but I am not able to match the projection with the others I have, primarily data downloaded from OSM (city of Boston). I read many articles, I have repeatedly tried to ...
2
votes
1answer
33 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 ...
2
votes
1answer
404 views

ArcGIS giving measured distances and the scalebar incorrectly

I am currently using ArcGIS 10.1 and am struggling to be able to measure distance or set a scale bar correctly. Its currently giving me absurd results orders of magnitudes to small (0.5m etc). All my ...
2
votes
0answers
170 views

Which of EGM96 geoid or WGS84 ellipsoid fits the earth better?

ImageCredit Question If we separately add up |H| and |h| over the earth surface, which of the sums come out smaller? Background There is a phrase in the tag description of "ellipsoid" that says ...
2
votes
1answer
99 views

What do different realizations of the same datum have in common?

Firstly, am I correct in assuming that the process of determining the shape and the size of the spheroid is independent from the process of determining the origin and the orientation? For example, ...
4
votes
2answers
78 views

towgs Definition for European Datum 1950

I am new to all things GIS so apologies for a basic questions. I am trying to specify the CRS of a climatic raster layer in R. It is an equal area projection based on Europe Equidistant Conic and the ...
1
vote
2answers
530 views

How to display WGS 1984 Web Mercator (Auxiliary Sphere) services in Google Earth?

The basemap services provided by Esri (on ArcGIS Online, Data and Maps for Sever, and the Data Appliance for ArcGIS) use the WGS 1984 Web Mercator (Auxiliary Sphere) spatial reference (WKIDs 102100 or ...
1
vote
2answers
365 views

Predefined Coordinate Systems missing in QGIS 2

in QGis 1.8 were lots of predefined coordinate systems (national projections). Where have they all gone in qgis 2.0? I specifically need the Gauß-Krüger-Projections Zone 1 to 5. Is there any plugin ...
0
votes
1answer
70 views

How to create shapefiles with z coordinate with QGIS

I'm working with QGIS, and I want to create a shapefile with the elevation coordinate, I can't find something similar to what I was used to do in Arcgis, can you help me? Thanks for your help Luís
1
vote
1answer
32 views

Description CRS EPSG:6372

does someone know where could I find a description of CRS EPSG:6372. I searched in the EPSG page but seem not to find something that quick.. Any help would be really appreciated. Regards!