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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2
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1answer
62 views

Can you create a CRS of superseded NSW Datum

I want to use a superseded projection (NSW integrated survey datum - referred to as ISG) because my main client utilises it. The projection is based on AGD66. We regularly receive survey files in this ...
2
votes
3answers
103 views

Geodesic measurements for short distances throughout US?

My ArcGIS experience has been limited to working on large-scale maps with planar projections. I'm moving to a project in which I want to calculate the distance between pro sports facilities throughout ...
0
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0answers
34 views

How to specify WGS84 CRS when importing a Shapefile into Idrisi?

Could you help me, please, to open shapefile from QGIS to Idrisi. I'm having problem answering to the Reference system, the project is using WGS84 but that is not in the Pick list. Idrisi is asking ...
0
votes
1answer
85 views

Why is shapefile layer not visible on WMS layer in QGIS?

In my QGIS project I have added a WMS layer for which the CRS is WGS84 EPSG:4326. Now I want to show my shapefile layer which has the same CRS. QGIS shows the layer separately but does not show with ...
1
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1answer
34 views

what is the relevance of cosine in determining map resolution? [closed]

"At any latitude and zoom level, you can determine the scale by using the following equation" Map resolution = 156543.04 meters/pixel * cos(latitude) / (2 ^ zoomlevel) is a quote from ...
0
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0answers
42 views

Issue on Setting Coordinates for SVG Map

Can you please help me to figure out how to set coordinates for BC Canada , based on following snippet. This code is setting coordinates for French as the 43.15710, 8.17199 is the lower right point ...
0
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0answers
48 views

I had an error in Gdalwarp and i don't know the reason

I was trying to warp a raster using a mask and shift it before clipping but when i exectute the command bellow in Qgis/PyQt using QProcess: gdalwarp -s_srs "+proj=merc +a=6378137 +b=6356752 ...
0
votes
1answer
66 views

Coordinate mix up

I am working on a basic map, pulling coordinates from google earth, converting them to decimal degrees in excel, and then importing them into qgis. I am using qgis 1.8. When converting from degrees, ...
3
votes
3answers
261 views

Can someone clear up a lat/long issue? with google maps/arcmap

I know a bit about lat/long, projected and geographic coordinate systems etc, and a bit about geodesy and datums, but I would like someone well informed to help me out. I have a lat-long in ...
0
votes
2answers
66 views

Which GEO data format does this data represent

I am parsing GIS data from a ESRI webservice in which I get the data specified as the following in a JSON file "geometryType" : "esriGeometryPoint", "spatialReference" : { "wkid" : 102100 an ...
0
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0answers
57 views

QGIS convert attribute table to point shape

I have imported an attribute (whith no spatial information) table from MySQL. Fortuantly it has two colums with Longtitude and latitude taken from google maps. Is it posible to use those values to ...
0
votes
0answers
98 views

How to export raster from ArcGIS for Desktop to MATLAB using Tiff without losing projection?

How do I export data from ArcGIS for Desktop and import to MATLAB using Tiff without losing projection (lat lon) information? ASCII is too slow for my application. I manage to export a raster ...
1
vote
1answer
160 views

Convert decimal latitude/longitude bounding box to SRID 26910

I have a bounding box specified in decimal latitude/longitude, and need to convert this into a bounding box in the SRID 26910 coordinate system. I've never had to work with different GIS co-ordinate ...
0
votes
1answer
111 views

How to support multiple Coordinate systems with ArcGIS Server 10.0 WMS?

I have a serve a number of wms Layers with ArcGIS Server (AGS) with the following coordinate system support - EPSG:25832, EPSG:31467, EPSG:4326 and CRS:84. As far as I can tell, AGS only supports 2 ...
2
votes
0answers
27 views

changing central meridian in QGIS causes problems [duplicate]

I want to change the central meridian of my world map (WGS84) in QGIS from 0 to -80. The problem is that this distorts the map every time I try it. This is what I do: go to Settings/Custom CRS ...
2
votes
0answers
30 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
93 views

Unknown coordinate system warning when programmatically adding layer

I have another interesting question for you. I have data with unknown coordinate system. When I add this data using a standard tool(File->Add Data) in ArcMap, a warning dialog appears. It looks like: ...
2
votes
1answer
43 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 ...
-1
votes
1answer
196 views

QGIS v2. Convert longitude/latitude to UTM projection-Zone 51J - Southern hemisphere [duplicate]

Could somebody please let me know in QGIS version 2.0.1 How do I convert Longitude/latitude default setting to UTM projection. I am bringing in waypoints from a GPS device which is set to the above ...
0
votes
2answers
206 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
0answers
19 views

Can't save custom CRS in QGIS 2.0.1

I am trying to enter a custom CRS in QGIS 2.0.1 but when I enter the proj4 parameters and hit okay they are changed. There is no save open in 2.0.1 which seemed to be the problem for many people ...
0
votes
1answer
63 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
vote
2answers
187 views

Add custom CRS - 2.2.0 Valmiera

i've builded a custom proj.4 library, tested it by command line (proj and cs2cs) and with postgres/postgis. All works fine. Now i'm trying to make the same with Qgis 2.2.0. I've replaced the original ...
0
votes
0answers
111 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 ...
-2
votes
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?
1
vote
1answer
142 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 = ...
0
votes
1answer
35 views

QGis polygon to points different CRS problems

I'm trying to join the values from polygons onto a grid of points. I had this problem solved here by @Underdark , however a few layers weren't working. It seemed they were all British National Grid ...
6
votes
2answers
485 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 ...
1
vote
1answer
67 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 = ...
2
votes
5answers
355 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
149 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
vote
1answer
105 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
votes
2answers
84 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 ...
1
vote
2answers
215 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 ...
0
votes
1answer
203 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 using ...
1
vote
0answers
68 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
votes
2answers
58 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 ...
1
vote
1answer
416 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 ...
0
votes
1answer
132 views

Get list of CRS in QGIS by python?

It is possible to get list/dictionary of "Recently used coordinate reference system" from QGIS by python? Or get list of all "Coordinate reference systems of the world" also from QGIS by python.
3
votes
1answer
69 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
96 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
177 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
138 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
139 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
124 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 ...
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vote
0answers
84 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
78 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
91 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
425 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 ...