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
74 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
29 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
41 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
62 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
26 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
22 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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votes
1answer
31 views

which projection are best for large continents [closed]

which projections are best for large continents and mid-latitudes
5
votes
1answer
54 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
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1answer
52 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
38 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
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1answer
53 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 ...
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0answers
46 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
36 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
41 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
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3answers
495 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
27 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
112 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
16 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
30 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
36 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
184 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
42 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
55 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
59 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 ...
-4
votes
2answers
60 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)?
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0answers
64 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
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0answers
64 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
85 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
49 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
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1answer
52 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
64 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
53 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
155 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
vote
1answer
62 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
106 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
votes
1answer
52 views

Reprojection issue from WGS84 to UTM32

In QGIS I want to transform a point shapefile from WGS84 to UTM32 (EPSG:4647). The result moves the point from somewhere in Norway to a position off the coast of Congo, Africa. Can anyone explain ...
2
votes
1answer
40 views

Does ETRS89 and UTM use the same zone (longitude and latitude)?

I'm building an app for the european country Denmark exclusively and I need to retrieve some geospatial data from a (geo)server. I'm currently trying to determine whether UTM and ETRS89 uses the same ...
1
vote
1answer
86 views

Choosing projection to make Arizona look “normal”?

I am having issues projecting my AZ state boundary from looking like this: to looking like this: I found that I could use the U.S. National Atlas Equal Area to get the shape I want, but when I ...
0
votes
1answer
60 views

Repositioning DXF Imported into QGIS?

I have a polyline drawing from AutoCAD that I would like to reposition manually, if possible. During my efforts so far it has been turned into both a tab file and shape file. The main source of ...
2
votes
1answer
77 views

Mapping out 3D points with QGIS2threejs

I have some points I would like to map out in 3D. The points were gotten from a GPS module athat was attached to a Raspberry Pi. This is the settings I used before starting qgis2threejs: This was ...
1
vote
1answer
54 views

Changing CRS in QGIS due to pop up window: "CRS warning! Warning: Input layers have non-matching CRS. This may cause unexpected results.” [duplicate]

I'm using GIS to map the movement of animals and their speed and density in different habitat types using shape polygons. When I got to the step ;Count points in polygon' a pop up window appeared ...
6
votes
2answers
65 views

Inferring lat/lon based on known location coordinates

I have a point dataset with a set of coordinates that is in an unknown projection. For some of these points I know the unprojected latitude and longitude. Based on these known data points, would it be ...
3
votes
2answers
44 views

Adding Excel file with degrees to map with CRS in QGIS?

How can I add a layer with X,Y in degrees (from an excelfile) to a map with CRS? I am using QGIS 2.8.2
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0answers
29 views

Same CRS but different units of raster cells in qgis

I have two rasters with the same CRS (WGS 84/UTM 34N). One is from a LiDAR scan and the other raster is created thru interpolation of point measurements by me. I would like to change the cell size to ...
1
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0answers
37 views

Convert Coordinate Notation tool

I am having trouble using the CCN tool. My data is a DMS 442315 1214598 and I need to be in DD to work with my county data which I know is in the correct format. I tried adding a new field then ...
3
votes
0answers
41 views

Choosing projection for routes that fall within two UTM zones? [duplicate]

I'm creating charts for routes that fall within two UTM zones; 30S and 31S. The offshore routes are in the Alboran / Balearic Sea - connecting Spain to Algeria. What projection should I use?
3
votes
2answers
93 views

What is a suitable map projection for the entire state of Idaho?

I am working with some sample GIS data for Idaho. The data is in geographic coordinates but I want it in projected coordinates. I am unsure how to address the issue of projection as Idaho crosses ...
-3
votes
1answer
62 views

Same coordinate system - shapefiles don't overlap [duplicate]

I have two shapefiles and two rasters (dem), and while I put them in the same coordinate system (Greek grid), it seems that they don't overlap. But one is the boundaries of a county, and another the ...