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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1answer
36 views

File representing extents of coordinates systems and their wkid

I'm looking for a file that represents the major coordinate systems throughout the world, and the extent that they cover. Ideally they'll also have the wkid as an attribute. Something like the ...
0
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2answers
73 views

I get an ERROR 000622 when it checks for arcpy.DefineProjection_management

So the purpose of my code is to create a loop that copies shapefiles from a folder to my folder and change its projection 'GCS_WGS_1984'. Each shapefile starts with the year follow by the month and ...
0
votes
1answer
46 views

Aligning two layers captured in different coordinate systems

I have two layers, one of points (locations of fruit trees) and one of Atlanta zip codes, in an ArcMap, but the layers are not aligning. The zip codes are in the top right and the fruit points are ...
1
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0answers
50 views

Understanding Scale and Resolution between WGS84 and Web Mercator

This might be very basic question, am trying to understand the relationship between scale, resolution and coordinate system. First, let me explain the problem I have a web mapping application (using ...
-1
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1answer
59 views

Why is it important to ensure that the shapefiles have a spatial reference system when created?

Why is it important to ensure that shapefiles have a spatial reference system when created?
0
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0answers
58 views

Error getting spatial reference as string in arcpy

I am trying to get the string associated with a spatial reference to print into an xml using arcpy and xml.cElementTree. Using the snippet: ... spatial_ref = arcpy.GetParameterAsText(3) ... Prj = ...
6
votes
2answers
358 views

What does coordinate system WG 21° mean?

I have a land survey document for a piece of land, it contains absolute coordinates that I would like to locate on google maps, but I don't know how to correctly interpret the data. What does the ...
2
votes
5answers
271 views

Is latitude / longitude a universal coordinate system?

I hear people complain: my biggest gripe with google spatial apis is that they hide the fact that latitude/longitude is not a universal coord system My question is Is latitude / longitude a ...
1
vote
1answer
57 views

Gdalinfo and QuantumGIS does not recognize Spatial Reference even though Python does

I apply the following Spatial Reference to a file: spatialRef = osr.SpatialReference() spatialRef.ImportFromEPSG(3411) outraster.SetProjection(spatialRef.ExportToWkt() ) geotransform = ...
0
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1answer
52 views

datum conversion with GDAL

I run gdaltransform like so: gdaltransform -s_srs nad27 -t_srs wgs84 -104.5 39.5 -104.5 39.5 0 gdaltransform -s_srs wgs84 -t_srs nad83 -104.5 39.5 -104.5 39.5 0 gdaltransform -s_srs nad27 ...
1
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1answer
40 views

Problems with french coordinate systems (i.e. Lambert Zone I, EPSG 27571)

I'm working on a coordinate library implementation and I seem to be stuck with the French Lambert coordinate systems. I'm using this page as a reference (can anybody confirm the results there are ...
0
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2answers
49 views

Calculate length of line across zones with at least m accuracy

I have created lines between multiple points that are across MGA 54 and 55S (EPSG 28355). I am trying to calculate the distance between points but different methods give different answers (~1km ...
5
votes
2answers
321 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, ...
0
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2answers
41 views

Define a projection for one point

I'm new to ArcGIS and am using ArcMap 10.1. I wanted to find the distance from a point (lat 36N long 12E) to all the polygons in my shape file. People on this forum helped me out and said that I ...
10
votes
3answers
1k 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: ...
2
votes
1answer
43 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 ...
1
vote
2answers
118 views

Why does Transverse Mercator projection have scale factor?

Why does the Transverse Mercator projection have a scale factor in ArcGIS and the standard Mercator projection not? In other words what is the difference between these two projections beside being a ...
1
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0answers
49 views

LLA vs ECEF--which to choose?

I will be providing points in 3D to an external source via XML. One coworker suggests Lat/Long/Alt and another suggests ECEF. We can do either without much trouble. We have an existing product that ...
0
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1answer
87 views

Calculate distance between two Coordinates to use in Variogram calculations in ordinary kriging

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 done using ...
0
votes
1answer
56 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 ...
1
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1answer
172 views

Eastings/Northings OSGB36 Grid origin

Using this site, we can see that the (approximate) centre of Southampton, UK has OSGB coordinates of 441847,112279. However, looking at the UK grid, where each large square is (500 km)2, then these ...
1
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1answer
77 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 ...
2
votes
1answer
59 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 ...
4
votes
1answer
102 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
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0answers
49 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 ...
0
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0answers
49 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
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1answer
47 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
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1answer
53 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 ...
7
votes
1answer
117 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 ...
0
votes
1answer
119 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 ...
7
votes
1answer
171 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 ...
2
votes
1answer
34 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 ...
0
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0answers
27 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 ...
3
votes
3answers
114 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
130 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 ...
3
votes
2answers
362 views

Where is list of Geographic Transformations in ArcGIS, and their areas of applicability?

I have some data in Provisional South American Datum 1956, and I need to project it to Web Mercator with WGS84 as the datum. When I use the project tool in ArcGIS desktop, it requires a Geographic ...
0
votes
1answer
41 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. ...
4
votes
2answers
74 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
29 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
57 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
151 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, ...
2
votes
3answers
1k views

Local Coordinate to Geocentric

The ultimate question, I need a transformation matrix to take a point in local space representing a roughly 500m x 500m place in New Mexico centered at -108.619987456 long 36.234600064 lat. The final ...
4
votes
2answers
457 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 ...
5
votes
2answers
624 views

Describing a coordinate system in arcpy

I have a python script in ArcGIS 10.1 which takes in a few inputs from the user. One of the inputs is a coordinate system. I would like to test whether the coordinate system the user chose was ...
1
vote
3answers
447 views

Formula/ calculation for ESRI map coordinate conversion (meter to decimal degrees)

I'm new to ESRI mapping. I have a set of points in ESRI, with x, y, z coordinates, which I believe is in meters. I am now writing an Android program, and I do not want to depend on ESRI, thus I would ...
2
votes
3answers
191 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 ...
0
votes
2answers
146 views

How can I find the SRID from the WKT out of a GRIB file?

I have a grib2 file which I'm trying to import into PostGIS 2.0 Raster and process. Trouble is, I can't figure out what the SRID is supposed to be, or one close enough for government work. Running ...
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2answers
53 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 ...
0
votes
2answers
70 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 ...
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votes
1answer
105 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 ...