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.

learn more… | top users | synonyms

2
votes
2answers
563 views

How likely is it that Smartphone Camera GPS coordinates are wrong?

According to the coordinates printed directly on this photo of my late son Kelvin here: https://www.dropbox.com/sc/w6tvwuvbosuh9rk/AADzT-3vDXcFQ9LnKK1BYMZUa ...and the Exif data from the .jpg: ...
2
votes
1answer
922 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 ...
2
votes
1answer
458 views

How do you calculate positional accuracy in qgis?

How to you compare two layers in QGIS to get the positional accuracy?
2
votes
3answers
690 views

C++ coordinate class that automates projection?

Can anyone point me to a C++ class for representing coordinates that automatically handles projection transforms? What I'm thinking of is something that would allow me to create vars that incorporate ...
2
votes
1answer
474 views

Convert Garmin or iPhone weird GPS Coordinates

I am trying to find a way to convert over 500 locations I have saved in my Garmin iPhone GPS app (iPhone 4S using Garmin StreetPilot v2.7), but I can't find a way to convert these coordinates as they ...
2
votes
2answers
381 views

Switch coordinates in linestring

I made a silly mistake: when creating linestrings in my PostGis database i inverted the lon and lat values. Which isn't a problem for postgis itself, but for my visualization and intersections. ;) Of ...
2
votes
4answers
977 views

Ordnance Survey 1 km Grid

I am wanting to get a copy of the OS 1km Grid layer. I have found these previous questions: Ordnance Survey grids - download or generate? and Ordnance Survey Grids But neither provide the ...
2
votes
2answers
3k views

Converting from local coordinates to coordinates GPS?

i am working with business object tool traying to make a kml file to be imported on google maps. I dont know much about geographic systems, but i begin to understand some basic things. I have a ...
2
votes
2answers
2k views

Converting OSM_ID to coordinates

I have downloaded some open street map data from Webgeo, but instead of coordinates it came with an "OSM_ID". I cannot seem to find any data dictionary or information about this variable on the web. ...
2
votes
1answer
499 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" ...
2
votes
4answers
1k views

Query Postgis Table with PHP

Would you be so kind as to help me with the following in OpenLayers. I need to be able to use the coordinates from a user click in a postgis query. To catch the coordinates of a click I built a click ...
2
votes
1answer
3k views

Convert X Y Pixels to Easting Northing

I'm trying to find out what the formula would be to convert the X, Y of an image to the Easting and Northing coordinates. I've downloaded some of the raster maps from OS UK web site and I'm looking ...
2
votes
3answers
3k views

Convert coordinates to geometry (polygon) using QGIS

I have an Excel sheet with grid data including geographical coordinates. I know that the coordinates represent areas, i.e., a multi(polygon). However, the data lacks geometry information. I'm looking ...
2
votes
1answer
2k views

Converting map coordinates using AutoCad to Excel sheet

I have some maps of pieces of lands and I want to convert the coordinates to excel sheet I want to arrange the data like this in the excel sheet: land number( the pink number in the pic) ...
2
votes
1answer
26 views

Wrong calculation of line start and end XY coordinates of a merged line- how can I fix this?

I have a feature class containing several rivers, which are derived from merging individual river segments to make a continuous line. They have been merged using the editor tool. I have calculated ...
2
votes
1answer
83 views

How to export a CSV with lat lon WKT from a layer which is not in WGS84?

I want to extract a csv with lat and lon coordinates so I select -- Geometry AS_WKT but when the csv is created I see this LINESTRING (277054.55782319931 198725.03588318737,277052.43701817648 ...
2
votes
2answers
273 views

How to calculate the distance between a line and a point (using lat/lon coordinates)

In my Android app, I need to calculate the distance from a point (the device's location, which is a lat/lon coordinate) to a line (defined by two lat/lon coordinates), and get the result in meters. ...
2
votes
1answer
148 views

Adding QGIS feature, that shows coordinates and scale, into a custom application

I'm writing a standalone application using PyQGIS and I'd like to add the QGIS feature that shows coordinates and scale as the cursor hovers over the map. I need to know this mainly in case of ...
2
votes
1answer
103 views

Creating a 5x5 poylgon in ArcGIS with a predetermined center with coordinates X, Y [duplicate]

I need to build a polygon (5x5 km) centered on a coordinate X,Y. I want to use this 5x5 square for an eventual clip. How should I proceed in ArcMap?
2
votes
2answers
7k views

How to calculate Distance, Azimuth and Dip from two XYZ coordinates

I have two XYZ coordinates and I would like to calculate the Distance, Azimuth and Dip between them. I have come across a similar question on this site that calculates it the other way around (with ...
2
votes
1answer
175 views

Calculating countries flown over on flight path

Say I have two airports given. I can then get their coordinates. Now that I have the beginning and end coordinates I can draw flight-path from the two locations. Now my question is that given two ...
2
votes
2answers
3k 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? ...
2
votes
1answer
41 views

Get coodinates from point shapefile

I converted a line shapefile to points as you can see in the attached image. Is there a way to know the coordinates of each point? Any help would be really appreciated! PD Im using QGIS 1.8.0
2
votes
1answer
2k 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: Latitude (S-N): -90 to +90 Longitude (W-E): -180 to +180 I have set the coordinate system of my ArcGIS data ...
2
votes
2answers
367 views

Loading GPS information into map and track waypoints?

I am using QGIS 1.8 in Ubuntu 12.04. I am working with Robot Operating System (ROS) and QGIS simultaneously. My ROS system is connected to LIDAR (sensors) that will publish GPS message so, I could ...
2
votes
1answer
181 views

Why does QGIS 1.8.0 crash when I try to set up CRS on Win XP?

I have a problem with my qgis 1.8.0. When I click on any button that set CRS or try to set the coordinates on the fly, qgis crash. I try to uninstall the program and re-install it again using ...
2
votes
2answers
849 views

How do I import specific Coordinates from Namibia in QGis?

I have a map here with Coordinates from the Schwarzeck Map Datum Format 1903. They have the following format e.g.: y: 41 944,31 x:363 810,71 I want these point to be pictured in QGis... how is it ...
2
votes
2answers
49 views

Which points in projected raster corresponds to certain latitude,longitude location?

What I have is a SRTM 3 arc-second raster file in WGS84 geographic coordinate system (here is that file). I then project it to the Azimuthal Equidistant projection with GDAL: gdalwarp -s_srs ...
2
votes
1answer
53 views

Coordinates calculation using QGIS

I am quite new to GIS software. I use QGIS. I have a question that might be trivial. I would like to derive the coordinates (Y and X) for an area. Just to make an example: I have two regions A and B. ...
2
votes
3answers
61 views

Identifying coordinate system?

I'm wanting to create a data layer using some open crime data from Salt Lake City, but I can't figure out the coordinate system they are using. See the link below to view the data. (You'll have to ...
2
votes
1answer
56 views

Unknown set of coordinates Northing Westing

I've been given a list of sites of vegetation with a "Northing/Westing" location e.g 52 43.569 - 001 44.833 I want to convert them to Easting Northing so I can load them into ArcMap. I've tried to ...
2
votes
1answer
56 views

Calculating Angle between two GPS Coordinates in QGIS

i'm looking to create an angle attribute inside a layer of points that has a starting coordinate and a finishing coordinate. The angle needs to be 0-360. Is there a field calculator command that I ...
2
votes
1answer
63 views

Is nearest search done on Euclidean plane accurate

I am writing a program which will find all the points within 1km. I am planning to to do this on a Euclidean plane as my database only supports Euclidean plane or sphere indexing ...
2
votes
1answer
560 views

How to calculate RMSE of geographic coordinates?

I've been working on my project and I stumble upon how I can calculate the Root Mean Square Error (RMSE) of geographic coordinates. What I have is a derived coordinates from processing LiDAR data ...
2
votes
1answer
731 views

Plot points on map using Fiona and/or Shapely

I have written a parser in Python that extracts the coordinates out of a GPX file and I would like to view those points on a map. I have done a little research and it seems like either Fiona or ...
2
votes
2answers
256 views

How to get cell value along Flow Direction

I have: a flow direction raster where I took off (assigned NoData value) the cells that overlayed the river network (from flow accumulation). a perfectly overlapping raster where I asigned a ...
2
votes
2answers
3k views

Converting between wgs84 and nad83

This is a newbie question that is about converting between wgs84 and nad83. I have aerial photos that I am trying to compute lat long coordinates for as closely as possible. There are several factors ...
2
votes
1answer
113 views

Understanding coordinates in Netherlands dataset?

I have data on specific addresses of companies in the Netherlands. The dataset also provides the coordinates but they look different from what I am used to see. I converted some of the addresses into ...
2
votes
1answer
211 views

Which EPSG for UTM with 8 digits in QGIS

I have a UTM datasets with 8 digits, so the first digits are 32 (for UTM Zone 32N), but which EPSG should I use to get the data at the right spot in QGIS in a 6 digits system. If I want to transfer ...
2
votes
1answer
315 views

Comparing two maps with two different libraries

I'm currently making a demonstration to compare the two OpenLayers libraries (2 and 3). For doing this, I have made two div elements and put the different maps on each other. The goal is to make a map ...
2
votes
1answer
43 views

Atributing fields in arcmap and excel

How do I populate a field in ArcMap (and Excel) with only a specific part of another field's attributes? For example: I want to populate the LATDEG field with only the degree part of a latitudinal ...
2
votes
2answers
246 views

How to draw a square from 2 coordinates?

I have a CSV file with the following output id, x min, y min, x max, y max, value 1 , 0 , 0 , 100 , 100 , 5 2 , 0, , 100 , 100 , 200 , 10 3 , 100 , 100 , 200 , 200 , 15 4 , 100 , 0 ...
2
votes
1answer
575 views

Haversine formula to calculate distance between real coordinates?

I need to calculate distance between two stations in a map in order to calculate empirical variogram in ordinary kriging to interpolate temperature data. Calculating distance in kriging using ...
2
votes
1answer
914 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
1k 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
1answer
291 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
581 views

Why is field calculator returning NULL for $x and $y in line and polygon layers?

I am trying to include XY coordinates in the attribute tables of several of my vector files; they are line and polygon files. I have tried two methods; first I used $x and $y in the field calculator ...
2
votes
1answer
495 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
2k 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
1answer
358 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): ...