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
269 views

Trouble using ogr2ogr w/ -s_srs to combine inconsistent EPSG files into my postgis DB

I'm having trouble combining shapefiles from TIGER and different local governments into a single postgis db to query legislative locations. I've imported all data to multipolygon geom, but found some ...
0
votes
1answer
101 views

Planar CRS for raster and vector layers

I want to work with a planar coordinate system, and as far as I know QGIS automatically puts me in a cartesian plan if I don't set up a CRS (Coordinate Reference System) for my project. That is ...
0
votes
1answer
177 views

How do I check spatial reference on all parameters during Tool Validation?

How do I check spatial reference on all parameters during Tool Validation? Just looking for recommendations. Here is what I have already. This must work with existing validation. import arcpy class ...
1
vote
0answers
144 views

LiDAR dataset displaying 500 meters to the east of correct position

Why does my LIDAR dataset show up ~500 meters to the east of the correct position even though a spatial reference/coordinate system is provided? Some background: The LIDAR data were downloaded from ...
1
vote
2answers
627 views

Myanmar Datum 2000 information

Does anybody know where I can find the technical details for Burma's latest datum? It's called Myanmar Datum 2000 and I can't find any details online. I need the details to create a custom datum on my ...
2
votes
1answer
54 views

How do I make this into a working CRS in ArcGIS?

+proj=tmerc +lat_0=0 +lon_0=-114 +k=0.9999 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs I have this text string which I successfully used to project data in QGIS. How do I use ...
1
vote
1answer
178 views

Question about BNG coordinate systems

I'm historically a user of MapInfo Professional but have recently started using FME and have been talked into now testing out a copy of QGIS. The main problem I've come across is that the coordinate ...
-2
votes
1answer
93 views

How to Draw/plot or identify in GoogleMaps with below PointData

How to Draw/plot or identify in GoogleMaps with below PointData? Below are the points generated from spatial cadastre software. PointName Xpos Ypos _1 341.0926 527.9615 _10 669.1454 ...
3
votes
1answer
193 views

Plotting spatial data when two spatial objects have different CRS

I have a spatial polygon object and a spatial points object. The latter was created from xy latlong data vectors (called latitude and longitude, respectively) in a dataframe, while the former was ...
3
votes
2answers
65 views

What is the closest CRS to “Meridiano de Greenwich”

I have a 1906 scanned map that I am trying to georeference in QGIS for Mac. The map has French and English lat-long, indicating them as either "Meridiano de Greenwich" or "Meridiano de Paris." I would ...
1
vote
1answer
89 views

Importing data into a project with a custom CRS incorrectly projected

I created a custom CRS for a project I am working on. I then started a new project, set to my custom CRS and turn on "on the fly" transformation. I import Rail data that I know is in my custom CRS, ...
1
vote
1answer
564 views

How to create polygon that goes over +/-180 (dateline) in ArcMap?

I want to create a polygon feature that will go through the dateline (180 long.) in ArcMap. I am using WGS_1984_Web_Mercator_Auxiliary_Sphere (WKID: 3857) for my data frame and my polygonal feature ...
2
votes
1answer
288 views

Wrong lon and lat

I am using QGIS 2.2.0! I have shape file with wrong coordinates, it's had replaced x coordinate with y coordinate. For example my point feature have coordinates: 4830698,7496859 and right coordinates ...
0
votes
2answers
233 views

Help, I have 10,000+ .shp files covering 3 UTM zones with unknown projections

I was handed a ton of property files with no projections attached but was told they are all in UTM zone 21S. Well once I merged them all together and projected them I realized that the data covers 3 ...
2
votes
1answer
181 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
446 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
votes
1answer
384 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
vote
1answer
40 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
votes
0answers
205 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
305 views

Scaling x,y coordinates in proj4

This question was asked before, but without answer. Let's say we have mercator map with given resolution (for simplicity in centimeters). Now let's get coordinates of (lat,lon) = (50, 15): $ proj ...
0
votes
1answer
277 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
2k 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
118 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
votes
0answers
122 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 ...
1
vote
1answer
367 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
418 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
32 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
64 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
115 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
52 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
3k 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
1k 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 ...
1
vote
0answers
42 views

Are ellipsoid and datum the same? [duplicate]

Are the datum and the ellipsoid the same? What is a Datum? The Earth is shaped like a flattened sphere. This shape is called an ellipsoid. A datum is a model of the earth that is used in ...
0
votes
1answer
170 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
294 views

How can I add custom CRS with +proj=mercxx to QGIS 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 ...
-2
votes
1answer
73 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
675 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
65 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
1k 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
117 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
603 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
688 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
626 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
192 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
571 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 ...
2
votes
1answer
531 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 ...
1
vote
0answers
118 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 ...
1
vote
2answers
110 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 ...
2
votes
1answer
2k 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
277 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.