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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6
votes
1answer
14k views

QGIS - Change unit of measure from degrees to meters

I am running QGIS 1.7.0 on windows, and I donwloaded a shapefile of census block group boundaries from TIGER. This file appears to be in the WGS 84 coordinate system, and when I open it in QGIS the ...
2
votes
2answers
553 views

Determining correct Coordinate System DHDN Bessel 1841

I am working on a data set and coordinates are supposed to be in DHDN Bessel 1841. Have a look here: https://www.pegelonline.wsv.de/gast/stammdaten?pegelnr=2330013 I created a shapefile with the ...
1
vote
1answer
253 views

How do you add a WKT specified coordinate system to Arcgis?

I've got a WKT specified coordinate system, how do I add this to ArcGis?
1
vote
1answer
1k views

MapGuide and Google Maps Coordinate System problems

I'm trying to do a simple MapGuide OS + Fusion overlaying Google Maps and I can't figure out why the coordinate system are off. I downloaded populated places from natural earth. After Googling, it ...
10
votes
3answers
2k views

Is the GEO tag for QR codes lat/long or long/lat

I just found out that you can add a geographic component to a QR code. I also just found you can create one on the Google Chart API using this: ...
29
votes
3answers
106k views

Does Y mean latitude and X mean longitude in every GIS software?

Now it's been 3 days I am using Mapinfo and it has Y as latitude and X as longitude. Is that the same case for all mapping software? As for any country their respective value is multiple of 1 or -1. ...
2
votes
3answers
4k views

Code to convert WGS84 coordinates to British National Grid Easting/Northings

I'm looking for some code, ideally C#, to convert a WGS84 coordinate to British National Grid Easting and Northings. Does anyone have this to hand? I tried converting the Javascript code here: ...
13
votes
3answers
4k views

Lon/lat transformation

First I should clarify I don't have previous experience with the field, so I don't know the technical terminology. My question is as follows: I have two weather datasets: The first one has the ...
16
votes
8answers
11k views

ArcCatalog 10.0 complains that spatial references don't match between a feature dataset and a feature class that have the same coordinate system?

I have a feature dataset that is using the GCS_WGS_1984 as the geographic coordinate system. It includes a few feature classes. This feature dataset is itself in a file geodatabase that contains a ...
0
votes
2answers
242 views

Can anyone help me to determine the coordinate system of an image I need to georeference? [duplicate]

Possible Duplicate: .shp with unknown coordinate system I need to capture spatial information off of an old map and I can't determine the coordinate system of the image. I also need to ...
8
votes
6answers
2k views

Looking for a tool to convert DD to DMS

I am looking for either an online tool or one that I can download to convert DD to DMS. For example, I want to convert from: 41.590833, -93.620833 to 41° 35′ 27″ N, 93° 37′ 15″ W ... Those are the ...
5
votes
1answer
1k views

How do I find the intersections of 2 circles on earths surface?

I have the circles' center in lat & long, as well as the radius in meters. How do I find the circles intersections? Edit: EXAMPLE: Circle 1: Center on Earth's surface (43.564627,-116.220524) ...
4
votes
3answers
567 views

Defining the appropriate Projected Coordinate System

I am a beginner at ArcGIS and have a technical question. I need to assign a projected coordinate system to my boundary/polygon data in order to calculate square miles. There are many to choose from. ...
8
votes
3answers
781 views

Longitudinal Issues with NetCDF data

I am seeking advice on working with world data sets where the GCS has a positive range (0 degrees to 360 degrees). The data I am working with are NetCDF oceanographic data and have positive coordinate ...
8
votes
1answer
4k views

getExtent() in OpenLayers returns strange values

I'm trying to get the bounding box of the map area displayed by OpenLayers. I tried to use map.getExtent() because it should be exactly what I need, but the returned values are "strange": For ...
2
votes
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 ...
3
votes
2answers
500 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 ...
1
vote
0answers
276 views

Spatial Reference and Area/Length Attributes relationship

I currently allow users to add a shape file in. From the shape file, allow the user to generate a new layer base on the polygons from the shape file's polygon they imported. Generating the new ...
2
votes
3answers
7k views

Change number of decimal digits for features in ArcGIS 10?

I am editing vertices in polygons and points in ArcMap 10, and realised that they only hold 3 decimal digits for the X, Y coordinates, but I would like at least 6 decimal digits. Even if I type in ...
5
votes
3answers
7k views

ArcGIS coordinate system

I'm developing some software using ArcGIS API, but the question is rather theoretical, as I just came from Google Maps and have no idea where to start; everything seems to be different including the ...
3
votes
1answer
464 views

Why are the formats of these coordinates different?

I'm really sorry if this is a silly question (and I'm sure it is) but I have tried searching but I am a complete newbie to coordinates and maps and I don't know what I'm looking for so am not finding ...
4
votes
4answers
9k views

Getting shapefile in right projection using ArcGIS Desktop? [duplicate]

I have an older map that I didn't create. I'm just trying to get everything to line up on it, and having a hard time. The data frame is in NAD_1927_UTM_Zone_12N, as are the point shapefiles (derived ...
-3
votes
4answers
703 views

Repository for .prj files

Do you know any repository where can i find .prj files? I am looking for local coordinate system: Warszawa 75 (Warsaw 75) I found myself this repository but the .prj which i found there seems to be ...
2
votes
1answer
8k views

Export list of coordinates in a points layer to spreadsheet?

This is similar to my previous question, but I would like to ask it for ArcGIS, instead of QGIS. If I am supposed to somehow merge the questions, please let me know. With an existing point feature ...
21
votes
5answers
25k views

Get list of coordinates for points in a layer?

I've got a layer in QGIS that is comprised of points. Its attribute table doesn't have (show) the corresponding x and y coordinates for each point. Is there a way for me to extract a list of ...
6
votes
4answers
487 views

Where should I start advanced GIS learning

I am relatively familiar with most of the GIS stuff. I develop GIS applications as well with open source offerings. Still I find some lapses in my theoretical knowledge in GIS. What resources can you ...
2
votes
1answer
97 views

Populate planet with data

i have a game that described a planet and is a sphere. on the client side, the world is separated to tiles (images) and i mapped it follow by this and this, so now when the user is zooming / dragging ...
6
votes
7answers
3k views

How can I digitize a PDF image?

I have an image file in pdf format which includes some drawings (lines, closed areas, and points). I want to digitize it into a shapefile so that I can show it on a Google map. I have a couple of ...
5
votes
2answers
4k views

Convert x, y position in georeferenced image (with world file) to longitude, latitude?

What steps do I need to do in order to calculate longitude and latitude for a specific pixel in a georeferenced image? For example this image ...
7
votes
2answers
5k views

How do I convert affine coordinates to lat/lng?

I am extremely new to GIS. I'm using gdal to read in a landuse/landcover map and I need to pick out the lat/lng of certain land cover types to index into a different dataset which is expressed only ...
10
votes
10answers
7k views

Batch convert lat longs to UTM?

I've got a .csv file that contains a long list of latitude and longitude points. Is there an efficient way to batch convert the list into a projected UTM coordinate system? Thanks.
33
votes
10answers
11k views

Identifying Coordinate System of Shapefile when Unknown?

I have a Shapefile but its coordinate system is Unknown, and there is no *.prj file. How I can identify it now? Are there any tools that could help?
4
votes
5answers
1k views

Converting LatLng coordinates to point shapefile

I have more than 50,000 LatLng coordinates defined under SWREFF99 1800 projection. I want to know, is it possible to convert these coordinates into a point shapefile ? if yes, then how can I do this ? ...
4
votes
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 ...
0
votes
1answer
411 views

How to transform a DEM to a cartesian coordinate system?

I am using the script r.inund.fluv. I run the script with all the required parameters and it produced a lot or errors. I emailed the author of the script and he said that "I think you are not ...
9
votes
2answers
3k views

Measuring distance in spherical Mercator vs zoned UTM

I've got points in WGS84 lat/long and I'd like to measure "small" (less than say 5km) distances between them. I can use the haversine formula from http://www.movable-type.co.uk/scripts/latlong.html ...
5
votes
1answer
2k views

Spatial Reference is null in ESRI Silverlight Map

I am using ESRI's Silverlight API to display a map with one dynamic layer. Occasionally (not always), when that layer is initialized, the SpatialReference attribute will be null. I'm not sure why ...
1
vote
2answers
873 views

Extracting lat/long from screen when using British National Grid projection in ArcGIS Desktop?

Using ArcGIS Desktop 10.0, is it possible to click anywhere on the map (projected to British National Grid), but return the coordinates in WGS84 lat long?
2
votes
1answer
308 views

Two rasters created from the same polygon have different extents?

My problem is that i am trying to export some rasters to Rockworks so that i can create a sand layer from them. Rockworks requires the grid files i use to have the exact same XY co-ordinates. So i ...
34
votes
4answers
9k views

LatLon or LonLat, what's the “right” way to display coordinates and inputs?

I'm trying to get a sense if this is an issue for others or every input/output should be labeled so user is not confused and just go with it? I think almost everyone pronounces it as "LatLon". Who ...
8
votes
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
votes
3answers
347 views

Global grid, which reference system to use?

I have seen a couple global studies using WGS84 as geographic reference, with the problem that the area of raster cells is not constant. Which reference system would you use for a global analysis in ...
20
votes
6answers
15k views

Defining projections for multiple shapefiles in ArcMap?

I have over 100 shape files that don't have .prj file and thus when I bring them into ArcMap 10 they show the coordinate system as unknown. I know all of the shape files coordinate system is GCS WGS ...
2
votes
2answers
467 views

Coordinate system in Map&Guide

One of my customers is evaluating transport planning software Map&Guide (http://www.mapandguide.com/) and what we require is to get the transport route data from their file to Garmin navigation ...
4
votes
1answer
2k 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.
7
votes
3answers
3k views

Writing world file when exporting TIFF using ArcPy Mapping?

According to documentation, the options are: Syntax ExportToTIFF (map_document, out_tiff, {data_frame}, {df_export_width}, {df_export_height}, {resolution}, {world_file}, {color_mode}, ...
5
votes
3answers
1k views

PHP MGRS Conversion Formula/Library

Currently, the formula I'm using to convert MGRS to Lat/Long and vice versa is giving me slightly different results than most other conversion utilities. It's usually between 10 to 30 feet off. This ...
3
votes
1answer
4k views

Lat/Lon/Alt to spherical or cartesian coordinates

On my previous question, it was advised I convert lat/lon/altitude to spherical or Cartesian coordinates. I'm not working near the poles and it would be safe to assume a spherical earth. What would be ...
5
votes
2answers
764 views

Quick way to determine if facing a given lat/lon pair with a heading

I'm looking for a fast way, preferably without trigonometric operations (just multiply, divide, add, sqrt and subtract) to determine if a point is visible. E.g. say I am facing 0 degrees N, I am at ...
5
votes
7answers
1k views

Problem with Swiss coordinate system overlay in WMS

I have administrative boundaries data for communities in Switzerland from SwissTopo. Original data came in shape files with 'Bessel 1841 Hotine Oblique Mercator Azimuth Natural Origin' projection. ...