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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2answers
51 views

Transformation from EPSG 31983 to EPSG 4326 change only one axis (R + ggmap)

I'm trying to convert my shape file with spTransform(), but it's not successful. I don't know why it's changing only one axis. I want to change the axis into decimal degree. # Libraries ...
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0answers
14 views

Inconsistent coordinates of centroid were found using the given value of radius of curvature in the prime vertical and in the meridian

I am currently writing a function on geodetic datum transformation in Hong Kong by referring to the Explanatory Notes on Geodetic Datums in Hong Kong by the Survey & Mapping Office of the Lands ...
5
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1answer
173 views

How do you check if two feature classes have the same spatial reference?

Using arcpy, how do you check if two feature classes have the same spatial reference? Just checking if the two are equal doesn't work: >>> import arcpy >>> fc1 = ...
1
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1answer
28 views

Grid clipping issue in Layout

I'm having an issue making a figure for a poster with ArcMap. I'm trying to make a grid that follows the map boundary in a Lambert Conical projection, and it's not coming out right. The map boundary ...
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1answer
294 views

Dynamic defining of transformation type for ISpatialReferenceFactory.CreateGeoTransformation call [duplicate]

Suppose given a point (IPoint) in some coordinate system. Required to transform it to another coordinate system. If both of coordinate systems are predefined, we can use IGeometry2.ProjectEx with ...
2
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0answers
34 views

Why is grid north so offset? [closed]

I am not a GIS professional, only a casual orienteering enthusiast seeking an explanation from experts. The plat of my property gives bearings and distances for each of the lines, as does the deed, ...
3
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1answer
91 views

Disparity between QGIS and ArcGIS for Desktop georeference results?

I am georeferencing a static map in JPEG format. I would prefer to use QGIS for a variety of reasons. I've never georeferenced with QGIS before, so I may not have the process quite right. I ...
11
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1answer
6k views

GDAL/Python: How do I get coordinate system name from SpatialReference?

In Python, using GDAL, I've extracted a raster's projection as a WKT string as follows: wkt = dataset.GetProjection() # wkt is ...
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1answer
46 views

Using Postgis spatial index in st_distance operation based upon explicit SRID column

I have two large tables with data that spans over multiple regions of the U.S and needs a defined SRID column in atleast one the tables to denote which coordinate system should be used for ...
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2answers
90 views

Why do my XY cordinates not make sense / show up in ArcGIS 9.3?

In the Add XY Data menu I selected to add a table containing UTME and UTMN coordinates. I selected a WGS84 projection b/c that's what the GPS device that meade the readings was set to use. However, my ...
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2answers
153 views

How to get an area Latlong geometry directly from google map?

I am new to field of GIS. I need to know that do we have an option of getting latlong of a building that we see in google earth or any Point of Interest areas. Something like i create & drag ...
2
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2answers
110 views

Converting shapefile CRS from WGS to UTM in QGIS

I want to calculate point distance but the result is null, and apparently it is because the point and the raster file have different CRS. The raster is UTM, and the point is WGS84 I follow the ...
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0answers
44 views

Intersect two same extent shapefiles, but got error 000117

I have used intersect(Analysis Tool) to intersect two polygon layers. But I got error 000117 after ran intersect tool. Same error message happened when I use clip (Analysis Tool). The answer and two ...
1
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1answer
28 views

Bent raster after Build Overviews for mosaic dataset using ArcMap?

I created a mosaic dataset from a set of 12 tiff's spanning the united states. Before running Build Overviews, the images all join together nicely. But after, they look like this: Any idea what ...
3
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1answer
33 views

CRS and QGIS georeferencing for Cassini projection

I have scans of OS 6" series maps which I understand are Cassini projection. According to an article my Mugnier, Photographic & remote sensing, Oct 2003 they had the typical scale factor equal ...
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0answers
67 views

DEM / Basemap Alignment

The image below shows the problem I'm facing. I'm trying to align a DEM with the ArcMap Imagery Basemap. Unfortunately, I can't make them to perfectly align. I tried changing the coordinate system to ...
0
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2answers
123 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 ...
2
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1answer
38 views

confused about distances on the wgs-84 ellipsoid

As far as I understand given a certain latitude the length of a degree of longitude is constant. So using any distance calculator (I use Mathematica here) this equals: (circumference of the earth) ...
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1answer
93 views

CRS transform from EPSG 4326 (WGS 84) ? to EPSG 27700 (OSGB 1936 / British National Grid)

I have a table which is an import of a shp file from www.geofabrik.de/ England > Roads. I've tried to change the CRS to EPSG 27700 but when I add this back to QGIS along side other layers which are ...
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1answer
1k views

How can I transform GCS_WGS_1984 to GCS_North_American_1983?

I need to convert a GCS_WGS_1984 data set to NAD_1983_UTM_Zone_14N. What transformation should I use?
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1answer
39 views

CRS confusion or georeferenced

I have georeferenced an old jpg map against Bing Road maps (OpenLayers plugin) and Raster>Georeferencer. I'm trying to use EPSG:4326 because my PostGIS database uses that. My PostGIS info shows ...
2
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1answer
57 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
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1answer
32 views

My point shape file having missing spatial reference information

I am using ArcGIS 10.2.2. I got a shape file with points representing spot elevations in my study area. This file has been provided by a third party institution. The coordinate system is missing ...
2
votes
1answer
41 views

Find coordinates of point on map

I have scanned map I know it scale and dpi. Is it possible if i know lon-lat cords of some point(X,Y) calculate lon-lat of another point (clicked) on this map? I have read some about georeferencing ...
2
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1answer
77 views

Clipping a raster with a shape layer fails by returning an empty raster (nan - 0)

I am trying to clip a raster layer by a shape define by a polygon. (A previous question was about a line layer clipping, whereas this one relates to raster layer) The resulting layer is however an ...
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0answers
22 views

Unknown coordinate system produced in 1980 by Japanese company in North Philippines

I am having the same difficulty with one of the report produced in 1980 by Japanese company. The grids format also N 38,578, E 41,400. The project is 390 kilometers north of Manila. I would like to ...
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2answers
150 views

Is WGS 84 datum, coordinate reference system, or both?

The background to this question is in Understanding difference between Coordinate System and Projection? There @mdsumner commented: WGS84 is not a cs, it's a datum. On a couple of places online ...
7
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1answer
254 views

Understanding difference between Coordinate System and Projection?

Can somebody please explain what is the difference between the Coordinate system (WGS 84 for example) and a Projection (Universal Transverse Mercator for example)? What is the difference between a ...
5
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1answer
517 views

Unknown Old Coordinate System of the Phillipines

I am reading a report made in 1979 and the coordinates show N 46,400 and E 47, 600. This is in the Philippines. Would anybody know what the coordinate system was used in this numbers? Thanks.
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1answer
39 views

How to calculate areas for data that covers the whole of Australia [duplicate]

I have a polygon shapefile showing mining areas across all of Australia. I want to calculate the area for each of the polygons however they have been provided in a Geographic Coordinate System ...
0
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0answers
24 views

Cordinate System Conversions

I have my council installations all in GCS WGS84 but they where mapped in Arc 50 coordinate system. When I display them on my Arcmap they do not coincide with the other layers such as roads and ...
0
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1answer
49 views

Coordinate Systems for tile packages used in Collector for ArcGIS

I have a geodatabase with multiple shapes, domains etc. Everything works fine in ArcGIS online and as well on the Collector for ArcGIS. For better performance while using a tablet for data collection ...
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0answers
14 views

How to find the angle of difference between two coordinate systems?

I am working on converting u and v components of wind from one coordinate system to another (WGS84 to NZTM2000). In order to do this I need to know the angle of difference between the axes of these ...
1
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1answer
68 views

Get distances between boundaries from an SpatialPolygon and raster pixels

I am trying to calculate the distance from several pixels of a raster to a boundary of some polygons in R as it is showed in the image. I have two problems: How to correctly define a boundary from ...
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0answers
32 views

Where can I download a world shapefile with 180-degree central meridian?

Does anyone know where I could download a world shapefile that has a projection with a central meridian of 180 degrees longitude? I have found the following question that provides instructions for ...
1
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2answers
83 views

How to find the intersection of three polygon layers in ArcGIS?

I have three data sets of San Francisco, TerraSAR-X, ALOS-PALSAR, Radarsat2. I have extracted KML files using Envi Sarscape. In order to find the intersection of these areas, I have converted ...
0
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1answer
19 views

Transferring coordinates unit from Imperial to metric in Arcmap

I have a raster with NAD_1983_StatePlane_Indiana_East_FIPS_1301_Feet coordinate. Is there any way to transfer the coordinate to metric in ArcMap?
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0answers
20 views

Layers do not overlap [duplicate]

I am new to ArcGIS. I have some layers. Three of them perfectly overlap and the fourth does not. I have tried with the Projection tool and I have tried so many things and nothing. When I check the ...
3
votes
4answers
434 views

Find CRS (coordinate reference system) based on known location and coordinates?

Is there any tool or any tutorial which would help me to figure out CRS (coordinate reference system) from related information? In my particular case I know only the system is in meters, has origin ...
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0answers
45 views

Formula for Nicolosi Globular Projection

What is the formula for the Nicolosi Globular projection? In other words, what is the function that maps the coordinate (φ, λ) on the sphere to the coordinate (x, y) on the plane? You can assume ...
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0answers
26 views

Figuring out how to work with state plane coordinate system

I am working with a physical map and we are currently learning about different coordinate systems and how they can be applied. I am really stuck on State Plane Coordinate systems. I have been ...
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1answer
57 views

QGIS: Converting Projection Coordinate Systems to Geographic Coordinate Systems to replace (X,Y) with Latitude and Longitude

So as the title suggests, I have a shapefile that shows a set of rail lines and I want to display each line independently so I extracted the nodes with Geometry Tools. Unfortunately these coordinates ...
0
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1answer
52 views

Changing coordinate system says that geotransformation is invalid?

I am planning on using the MODIS burned area products which were produced by Maryland University. These come as either polygons or rasters. In the user guide it says A shapefile version of the ...
1
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3answers
211 views

What is the Origin of WGS84 UTM 18N?

I was given an unprojected coordinate in the form of lat, lon and I am using pyproj to convert to projected coordinate as such: from pyproj import Proj # New Jersey lat = 40.704895 lon = -74.094994 ...
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0answers
68 views

Geographic vs. projected raster cell size area

I am wondering the best way of knowing how to define the area of each raster cell in global data. Specifically, I downloaded all ~400 tiles of MODIS land cover data, mosaiced them into one, and now am ...
1
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2answers
96 views

Coordinates not displaying in UTM

Mac OS 10.9.5; QGIS 2.8.4-Wien; offending data here I want to calculate the centroid of a polygon in meters. However, I cannot get QGIS to display in UTM and I cannot transform/project the data to ...
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0answers
30 views

proj4js with geocentric CRS

I am developing a little web app to transform coordinates between CRSs. To do that I am using proj4js, but I notice that proj4js can't work with geocentric CRSs. Is there another tool similar to ...
1
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0answers
18 views

Points in Polyon with two different CRS using QGIS? [duplicate]

I'm relatively new to QGIS. I've got a layer that shows the boundaries of the wards in the UK. In addition to this, I've got a csv file, which has long/lat plus an answer (binary). The problem is, ...
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1answer
697 views

Layers are of same area but they do not overlap in ArcMap like they should? [duplicate]

For my GIS project for my class, I have downloaded several vector layers from different websites (polyline of the continental divide, a boundary polygon of New Mexico, a rivers and water bodies layer ...
1
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1answer
92 views

Getting inaccurate results converting from New York State projection to NAD83 with Python's pyproj

I've been trying to do a standard coordinate translation between New York State Long Island (ESRI:102718) and latitude/longitude (EPSG:4269)...but I keep getting the wrong lat/lng results. I don't ...