Any of a set of two or more numbers used to determine the position of a point, line, curve, or plane in a space of a given dimension with respect to a system of lines or other fixed references.

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2
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1answer
162 views

Moving a shapefile point to specific coordinates

In QGIS is there a simple way to move a shapefile point in a shapefile point file to specific coordinates? Without exporting the points to WKT changing the x,y values and then importing the WKT via ...
2
votes
1answer
120 views

How do I calculate the coordinates of the median point of a polyline?

I have a shapefile with some polylines. For each one of these polylines I'd like to calculate the median of the polyline (i.e. the point that's equidistant from each end) and then, calculate its ...
2
votes
1answer
172 views

Adding UTM Zone Number to Coordinates

The computer program that I'm working with requires an 8 digit UTM Easting for the coordinates of shapefiles (i.e., the UTM zone number must be included with each coordinate within a shapefile). The ...
2
votes
1answer
109 views

Looking for a tool that will place the cursor to a specific x,y coordinate

I am a new user to Quantum GIS. I am looking for a tool/function that will allow a user to type in coordinates, and place the cursor on that exact position. This is for navigation in the field... ...
2
votes
1answer
100 views

Is it possible to update only latitude or longitude in postgis ?

I have a postgis database that contains Points created based on a couple (longitude, latitude), and I need to update only one of those two for a given point. I found that it's possible to do so but ...
2
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1answer
167 views

Calculating points in the USDA's Cropland Data Layer coordinate system

I need to integrate against the USDA's cropland data layer. They've got a demo and some API docs. The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537): ...
2
votes
2answers
894 views

Extract coordinates from vector layer in PyQgis

In Qgis, I have made a polygon, and from that polygon I have made a vector grid via research tools-> vector grid. The grid covers the entire polygon. Now I want to extract these grid points in the ...
2
votes
1answer
75 views

Latitude and Longitudes are replaced with zeros when importing excel 2007 worksheet into personal geodatabase

I am trying to import an Excel 2007 data set into a personal geodatabase so I can convert coordinate systems. The data set includes point locations in Decimal Degrees. When I import the Excel ...
2
votes
2answers
430 views

How to transform Lambert coordinates in C#?

I want to transform Lambert (EPSG:3035) coordinates to EPSG:4326 in C#. I have tried this: var lambert = cf.CreateFromWkt("PROJCS[\"ETRS89 / ETRS-LAEA\",GEOGCS[\"ETRS89 ...
2
votes
1answer
1k views

How to make a predetermined Polygon (Circle) From 4 Coordinates, The Radius and Center Longitude and Latitude in Openlayers

I know how to make a predetermined Polygon in Openlayers (see below). Please have a look at http://studio.netnrg.co.za/dev/rnd/blake.loizides/openlayers var feature2 = new ...
2
votes
1answer
506 views

Looking for a pure Python method to convert Lat/Long To MGRS

Does anyone know of any packages out there that implement a pure python method to convert lat/long coordinates to MGRS coordinates? PyPi has a package, but it requires some c-extensions from ...
2
votes
1answer
136 views

Adding graticules to the edge of the map only in QGIS

I would like to add graticules to a map, once it is in the 'print composer', on the border of the map, and not on the frame (my map insists on being smaller than the frame). I have managed to add a ...
2
votes
1answer
98 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, ...
2
votes
1answer
163 views

How to smoothly join two rectangles

I am looking for the Math and steps involved not using a tool. We have PostGIS but its an old version so we are working with the data in Python. Given three coordinates: -107.37, 52.46 -103.24, ...
2
votes
1answer
185 views

How can I show points on the same coordinate as e.g. a bigger symbol in QGIS?

I use QGIS 1.8 for mapping archaeological findings. Some of the findings within one layer are located on the same site and therefore have the same coordinates. Therefore you just see one point instead ...
2
votes
4answers
416 views

Get coordinates from address

I am writing a application which allow users to save a address into database (db) and in the next step it shows all addresses on a map. But in the saving step I need automatically calculate a GPS ...
2
votes
1answer
821 views

Understanding the difference between coordinates projection in OSM and Google Maps

I'm looking at the coordinate differences between Google Maps and OSM. I'm a noob in the technicality behind GIS. Having read: EPSG 3857 or 4326 for GoogleMaps, OpenStreetMap and Leaflet How to ...
2
votes
1answer
184 views

How to flip X and Y coordinates of a grid by GDAL

I have a grid, which has flipped X and Y coordinates (X is represented by Y values and Y is represented by X values). This results in grid being positioned in completely wrong place. How can I flip ...
2
votes
1answer
3k views

Trying to set the OpenLayers MouseOver position to be outside the Map

This is my code and I am trying to obtain the MouseOver to be displayed outside the Map container. <!DOCTYPE html> <html> <head> <title>My Map</title> ...
2
votes
1answer
1k views

How to find bounding coordinates (lat/long) for UTM zones?

I want to error check incoming lat/lng points by checking if the point resides within the given UTM zone. (This would work for the data im using because sometimes there is a missing sign or lat/lng is ...
2
votes
1answer
539 views

Read .DEM (USGS) FIles with C#

I have a huge number of .DEMs and have been investigating how to process them into something useful. Does anyone know how, or even if it is possible to read coordinates and elevation data from ...
2
votes
0answers
17 views

Choosing the map scale (1:nnn) for the given raster dimension

Starting points: let define the raster image size, say: 1800x900 pixels I want draw my own raster image map - by drawing polygons e.g. like "draw line from pixel with coordinates x100y100 to pixel ...
2
votes
0answers
35 views

Decimal degree coordinates: how many decimal places to use for …? [duplicate]

When using coordinates in decimal degrees, how many decimal points actually make sense? For example, say one is producing a table of locations of base camps in a report, there's no point in ...
2
votes
0answers
29 views

Is it safe to store coordinates on NFC tags always in one CRS and rely on conversion for others

I'm involved in NFC (Near Field Communication) standardization of a record structure for geographic point locations. That will allow to put coordinates on NFC memory tags which can be read with a ...
2
votes
1answer
103 views

Determine when I have crossed state line?

We are currently using the Google Maps API to get route information and total mileage but we would like to determine when we are crossing into a new state. When we return the route information we can ...
2
votes
0answers
156 views

How to add XY coordinates (latitude/longitude) to a DEM raster in ArcGIS 10.1

I would like to add xy coordinates of about 10 sites to a raster. I am using ArcGIS 10.1 and my xy coordinates are on Access 2013 database - saved as .mdb. The steps I have taken so far: 1) In ...
2
votes
0answers
76 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 ...
2
votes
0answers
108 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
0answers
164 views

PyProj/Proj4 convert geographic to projected coordinates for Geostationary Data

I am trying to convert geographic coordinates (in degrees east/north lon lat) to projected coordinates in meters for geostationary full disc data (GVAR Goes East data from CLASS). To do this, I tried ...
2
votes
0answers
269 views

How to limit a specific area in order to have a topographic 3D map using MatLab?

I am using MatLab, I want to build a topographic 3D map, I am following this guide, I have been doing the steps listed on the section Draping Geoid Heights over Topography, and I do not have any ...
2
votes
0answers
183 views

Plotting X, Y coordinates generated from MySQL database in QGIS

Currently running QGIS 1.8.0 on Mac OS X 10.8.4. I can plot points on a map using the "Add delimited text layer" plugin to get x-y coordinates from a text file. However, I'd like to be able to ...
2
votes
0answers
89 views

Should 2D Positions and 3D Positions be considered conceptually different entities?

Let's suppose we want to model GeographicPositions, described by coordinates or coordinate tuples inside some Coordinate Reference System. Also, these would be put inside some sequence to represent ...
2
votes
0answers
135 views

Comparing two spatial datasets statistically

I'm new to this forum. I'm working on the following problem - I have two datasets. Let's call it dataset A and B. Both of them will contain a set of points like A1,LonA1,LatA1 A2,LonA2,LatA2 .. .. ...
2
votes
1answer
606 views

Getting polygon shapefile node coordinates and point order

I am trying to get the coordinates of each node of a polygon in QGIS. What I basically did is use the following tools: Vector -> Geometry tools -> Extract nodes Vector -> Geometry tools -> Export ...
2
votes
0answers
104 views

Interpolate current Course value of GPS using previous Course values

I have a set of GPS data with Lat, lon and Course. I need to interpolate current value of course, using previous values of Course. The formula I am using is not accurate in curves.In C language I was ...
2
votes
1answer
761 views

Plotting latitude on to a (Mercator projection) SVG representing a country map

I want to convert (google sourced) longitude and latitude coordinates to x and y to place points on a SVG map I can get the longitude converted to X but I can't nail latitude. ...
1
vote
1answer
798 views

Change coordinates of a polygon

I wanted to know whether it is possible to change the coordinates of a Polygon by typing them in. I don't want to have to manually drag them into the right position.
1
vote
2answers
133 views

Coordinates values change for ArcGIS

I have received thousands of location information like below. X= 10°52.579 Y= 078°38.473 I don't have idea in which format is this, please let me know what is the format of this location and ...
1
vote
2answers
274 views

How to remove z & m coordinates from shapes with QGIS? (Or arcgis, grass, gdal, Python…)

I've recently received some parcel data in shapefile format that has z & m coordinates (all = 0.0). The WKT for a typical parcel looks like this: "MULTIPOLYGON (((2672464.560700002 ...
1
vote
1answer
367 views

EPSG:4326, EPSG:3857, JOSM and unprojections

It is said here that EPSG:4326 is not a projection. In my mind, a projection is a transformation of the surface of the Earth producing a flat image, notably a bitmap. We know that WGS84 (World ...
1
vote
2answers
370 views

How do you convert to degrees and minutes from 8/9-digit lat/lon DMS code? [duplicate]

I'm trying to map the national bridge inventory, but the coordinates are stored in this 9-digit code for longitude (and 8-digits for latitude) EXAMPLE: Longitude is 81°5.8' Code is 081054800 Page 9 ...
1
vote
1answer
539 views

How to compute mean coordinates?

Can anybody explain how to compute mean coordinates? Regards.
1
vote
1answer
103 views

How to write a expression in field calculator for finding $X and $Y?

I'm trying to calculate the lat/long of points using the Q GIS field calculator.Nathan W suggested to First, save the layer as WGS84 and import it again. Then in the field calculator you can use $x or ...
1
vote
1answer
199 views

generate random world point geometries

I have a world map. I need random point geometry. So, how can I randomly generate point coordinates? Any programming language. Also, I am using SRID 4326. Any programming language.
1
vote
2answers
85 views

Changing layer extent to decimal degrees?

Using ArcMap or ArcGIS 10 ... In the photo below, you can see my extent is in meters while my projected coordinate system is in decimal degrees. How can I convert my layer extent to decimal degrees? ...
1
vote
1answer
132 views

How to find nearby objects using Easting and Northing range

I have a bunch of objects which have associated Eastings and Northings in format OSGB36 for example: 265397 869562 547297 179002 If I have a starting Easting and Northing, and wanted to find ...
1
vote
2answers
58 views

qgis polygon to coordinates

I have the ordnance survey postcode polygons, i can get the centre point on the postcode (Using polygon centroids) and all the corner coordinates (using extract nodes) Does anyone know how to export ...
1
vote
1answer
52 views

Draw an item from coordinates in QGIS?

Is it possible to draw a line or to draw a triangle or another figure by digit the coordinates of the vertex? I use QGIS 1.8 on windows 7 system.
1
vote
1answer
359 views

Leaflet Custom menu links

I have an issue where leaflet when embedded in Drupal will not allow the user to click on the map as the Y coordinates have a decimal on for some reason. As a quick fix, I am thinking to put the map ...
1
vote
1answer
139 views

If I've given two different layers the same CRS, why won't they overlay one another?

I have a "towns" and "state" shapefile for Massachusetts as two separate vector layers in QGIS. I've set the project coordinate system to WGS 84 at the bottom of the screen (next to the "coordinate" ...