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
47 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 ...
0
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1answer
22 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 ...
7
votes
1answer
274 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 ...
1
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0answers
47 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 ...
1
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2answers
92 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 ...
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0answers
27 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 ...
1
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1answer
67 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
59 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 ...
13
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2answers
563 views

Which projection is this data in?

I received a shape file for my project from an agency and was told that they always use UTM. However, the values have too many digits for being projected in UTM. min max x 32507319 ...
1
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0answers
37 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
77 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
119 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 ...
1
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1answer
97 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 ...
0
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1answer
32 views

How to read info from the CRS? [duplicate]

I'm struggling to understand how the geo projections work in practice. The info a the CRS is as follows: {'ellps': 'WGS84', 'no_defs': True, 'proj': 'longlat'} Does it mean that the coordinates are ...
0
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0answers
23 views

How to work with a shapefile that has no projection information? [duplicate]

In a shapefile I'm working with there is no information on the projection used. That is, no .prj file. Is there a hack/alternative way of determining what coordinate system the data is in?
0
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1answer
51 views

Failed to export vector file from OGR?

I use to transform data points from UTM (WGS84) to WGS84 EPSG:4326. Basically from UTM to Geographic coordinate system both in (WGS84). I tried to do it again but an error message appears. ...
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2answers
100 views

Layers with same coordinate system still do not overlap, as they should, even after ArcToolbox Define and Project tools [duplicate]

For ArcMap 10.3: I had two shapefiles, that at one point, were in different coordinate systems. Shp#1 was in NAD_1983_Texas_Centric_Mapping_System_Albers and Shp#2 was in ...
0
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1answer
35 views

two layers with same projection do not overlap [duplicate]

I have a boundary layer for an area. the layer properties are top: 4431527.680136 m bottom: 4431199.984995 m left: 569103.516495 m right: 569438.079758 m Projected Coordinate System: ...
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0answers
27 views

EPSG:4978 or others for Distance

Usually when I have been calculating distances I project to the system which has the tightest crop around my points e.g. for the UK #http://epsg.io/27700-5339 (accuracy: 1.0m) uk = '+proj=tmerc +...
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1answer
32 views

which projection are best for large continents [closed]

which projections are best for large continents and mid-latitudes
5
votes
1answer
56 views

How do you display latitude \ longitude coordinates in ArcGIS?

I would like to display latitude and longtitude coordinates (at the bottom of window) for my data which I am editing in different coordinate system. Is it possible?
2
votes
1answer
58 views

QGIS Pre-set CRS/projections missing/unavailable

I am using QGIS 2.0.1 running off of a Ubuntu computer. I have been going through some basic tutorials (http://fossgeo.org/free-qgis-courses/) and have come up against a small and silly little ...
1
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0answers
49 views

Python error when using r.reclass on raster with no CRS

I have a set of GRID data (directory of .adf files) that I'm trying to reclassify in QGIS. I'm using the GRASS r.reclass function to try to reclassify the layers, but GRASS keeps failing and ...
1
vote
1answer
55 views

Coordinates are wrong [duplicate]

In QGIS 2.13.2 I have a google map and a shapefile. Now I want to print it with all the necessary items, but I have a big problem with the coordinates. First of all, the coordinates just appear when I ...
0
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0answers
56 views

Why is the project tool in ArcGIS (ArcMap) for desktop throwing the “invalid geographic transformation” error?

I'm trying to reproject a point shapefile from ITRF92 to WGS84 UTM ZONE 14 NORTH. On the geographic transformation input field, I copied and pasted the following geographic transformations from the ...
1
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1answer
40 views

Leica Cyclone 5.1 TLS Data referencing using Trimble DGPS

I am using a Leica HDS3000 Terrestrial Laser Scanner (TLS) and Cyclone version 5.1 to acquire and process point clouds. Within the manual for Cyclone 5.1, Leica mentions that a user can enter the ...
0
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0answers
46 views

Coordinate system for the State of California

I need to calculate, for the whole state of California, the hectares per type of crop. To do that, I have to project my layers. Because I need to work with all of the area of California, I think I ...
12
votes
3answers
500 views

Does transforming to a new projection, then back, affect data accuracy?

I have a feature class (South Carolina counties, so a fairly large geographic area) in NAD83 SC State Plane. It needs to be transformed to a second projection (NAD83 UTM 17), then transformed back 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, ...
1
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1answer
40 views

Projected Coordinate System for South Australia

I am calculating areas of polygons and distances between points in a small park in South Australia (~ 139.4 longitude, -34.3 latitude). All of these points are currently in GCS WGS 1984, and the ...
1
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2answers
124 views

Why do my points end up in Africa? (should be Croatia)

I have the correct coordinates in a excel file, but when I import the file, the point always goes to the wrong place. (I need it in Croatia, and it puts the point in Africa) I've tried chaging CRS ...
1
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0answers
17 views

Export/print QGis: dismatching OSM data on an OSM-layer

On QGIS (2.10, winXP). is there any known problem by exporting or printing .osm-data (from JOSM) onto an Openstreetmap-Mapnik-layer? The imported waypoints always shift from the left less and less ...
4
votes
3answers
35 views

gdalwarp to geographic coordinate system

I'm getting the folllowing Error when trying to re-project a raster from NAD_1983_Albers to GCS_North_American_1983. I used the proj4 defenition from going to Properties in QGIS of the layer whose ...
1
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0answers
56 views

How to perform statistical test for two sets of points?

(I have asked this question originally on Cross Validated; however, no good answer and someone suggested me to ask the question here). We know that we can perform statistical test (e.g., t-test) for ...
1
vote
3answers
227 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
63 views

Updating mapnik stylesheet to render WGS84?

We have a production tile server loaded using osm2pgsql serving osm-bright, osm-carto and osm-mapquest style tiles and would like to be able to server those in WGS84 projection, as well. I've tried ...
3
votes
2answers
61 views

PostGIS raster - [x,y] from lat/lon

I have coordinates in [lat, lon]. How can I convert them to the rasters "pixel" position [x, y]? I know raster top-left corner, scale and skew.
2
votes
1answer
62 views

How to display different layers with different CRS in one canvas in a standalone application?

I am a freshman of the pyqgis. Now I load the raster and vector data in the standalone application. The two data are same area, but in my canvas, they are at different places. I want to know how to ...
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votes
2answers
63 views

Projection for using ArcGIS as CAD [closed]

I want to use ArcGIS to map my apartment. How can I create a projection file (with which parameters)?
1
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0answers
98 views

In OpenLayers 3, transformExtent to EPSG:8155 produces error

I'm trying to get the extent of a map using OpenLayers 3, so that I can use it in a CQL filter to limit the area of the WMS request to the area currently shown in the map extent. To do this, I have to ...
2
votes
0answers
104 views

Find gravity normal by ECEF or GPS coordinate of point

How to find gravity normal by ECEF or GPS coordinate of point? Is it the same as normal to elipsoid? Is this ordinary way to calculate normal to ellipse? I'm not quite sure which altitude is ...
4
votes
1answer
120 views

convert lat/lng to pixel and vice versa

This had been asked previously on Stack Overflow. I've tried different methods/formulas but results are not correct. 40.764296,-73.97302 should result into 930,3590 pixel on map image. I've Manhattan ...
1
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0answers
55 views

Choosing CRS to use for South Africa that will give map scale in meters in QGIS?

This has been a constant source of frustration for me. I can't seem to always get my map scale in meters in QGIS, even if I use a CRS that has map units of meters, e.g. Alberts Equal Area and others. ...
5
votes
1answer
61 views

Shapefile projections not matching up in QGIS?

To start off with, I'm very new to QGIS. I'm attempting to place a shapefile with locations for 3 substations on a map of Peniche, Portugal. The locations for the substations are given in latitude and ...
3
votes
2answers
76 views

How to re-project a shapefile to be compatible with another shapefile or raster?

I have a polygon shapefile and a raster. The shapefile and raster have different coordinate systems. Coordinate System for the shapefile: NAD_1983_UTM_Zone_19N WKID: 26919 Authority: EPSG ...
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votes
1answer
76 views

How to check based on GPS coordinates if point is near a given path? [closed]

Path is just a straight line defined by coordinates of the beginning and end of it. My coordinates are simply longitude and latitude of three points: start of the path end of the path my point (for ...
6
votes
2answers
178 views

Is a Helmert transform necessary to convert between WGS84 and NAD83?

I've read things all over the internet which claim that NAD83 and WGS84 are effectively equivalent (with minor ellipsoid differences). However, if I do geodetic (WGS84) -> ECEF -> geodetic (NAD83) ...
1
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1answer
76 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 ...
2
votes
2answers
191 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 ...