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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17 views

3ds Max file of a cityscape import into ArcGIS

I imported a 3ds Max file into ArcGIS Tools/3D Analyst toolbox/Conversion toolset/from File toolset Coordinate System(optional) I use the given projected spatial coordinates but the file is drawn in ...
1
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0answers
28 views

How much error is should occur when using WGS84 to ECEF coordinates?

The method is not recommended for distances larger than 4km. I am getting reasonable accuracy in terms of the east and north bearings, but for the up direction I am getting error upwards of 1km for ...
15
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8answers
495 views

Seeking introductory texts about coordinate system projections?

Even after some time working in this GIS field, I still don't have a solid understanding of spatial references, how they are projected, and most importantly, if you still need to worry about the fact ...
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1answer
28 views

Understanding ordnance grid reference such as TQ38-7152-9751?

I have a list of OS grid references, such as TQ38-7152-9751, which I assume is at a resolution level below 1km, but cannot find a grid for this or a way of converting to eastings and northings?
57
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3answers
78k views

Algorithm for offsetting a latitude/longitude by some amount of meters

I'm looking for an algorithm which when given a latitude and longitude pair and a vector translation in meters in Cartesian coordinates (x,y) would give me a new coordinate. Sort of like a reverse ...
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2answers
34 views

Wrong length of edges

I want to make a network analysis with ArcGIS. I am using openstreetmap-data from the Geofabrik but I have big problem: The length of my edges are not the right one. The length of the edge is for ...
0
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1answer
54 views

How to convert shapefile of India into a system with longitude and latitude system?

I have two shapefiles of India. One is without PoK and other is with Pok. I want to convert the shapefile of India with PoK into a co-ordinate system with longitude and latitude (same as without PoK). ...
6
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3answers
13k views

Using ArcMap, how may I convert a shapefile to use decimal degrees?

I have a shapefile that currently uses meters as the measure for its coordinate system, but the map framework I wish to use expects decimal degrees. I'd like to reproject my shapefile to use decimal ...
2
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3answers
950 views

What are the differences between 81989 and 27700 CRS for the British National Grid?

We are using Oracle Spatial to run point in polygon queries in Great Britain using Ordnance Survey MasterMap and point data. MasterMap is on British National Grid (BNG) and has the Coordinate ...
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0answers
20 views

Multiple UTM Zones in a geodatabase [duplicate]

I am currently setting up a geodatabase for the province of Alberta. What would be the best practices for implementing a provincial geodatabase (ArcSDE/SqlServer 2008 R2) that happens to fall within ...
0
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0answers
51 views

Map Projections - WHAT?

I have a problem (C#.NET): What I have: Points with a coordinate (Lan & Lon) A canvas (WPF) with a dynamic size A control which represents a point A zoom factor, the kilometres from right to ...
7
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2answers
4k views

How is EPSG:4326 data 'projected' in a 2D map?

I like to think I'm relatively well-versed in datums, projections, and coordinate reference systems, so if this is a stupid question I will suffer eternal shame. OpenStreetMap data is stored in WGS84 ...
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0answers
13 views

Two layers of the same region with the same coordinate system does not lay in the same place! [duplicate]

I know that my problem seems to be frequent but I couldn't find any good till answer. I have two layers for the same place (area and roads) in my ArcGIS, both of them has the same coordinate system ...
6
votes
2answers
730 views

Getting the projection of a LAS file using liblas?

I am using the python api of liblas to read/write las files. I would like to get the spatial reference information of the las file using liblas, but have been unable to figure it out. Can anyone ...
1
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1answer
24 views

Export entire Mosaic with “Equal-Arc” spatial reference

I have several mosaic datasets contain a total of about 1000 images, each about 500mb in size. Unfortunately our customer needs a file format different than the one we are using and needs the imagery ...
173
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11answers
62k views
2
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0answers
60 views

Change coordinate system to add buffer in meters

I have am trying to add functionality to allow users to find points that are within a buffer distance inside or outside the parameter of a polygon. The map is in IProjectedCoordinateSystem so to my ...
45
votes
4answers
186k views

Does Y mean latitude and X mean longitude in every GIS software?

Now it's been 3 days I am using Mapinfo and it has Y as latitude and X as longitude. Is that the same case for all mapping software? As for any country their respective value is multiple of 1 or -1. ...
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0answers
21 views

Importance of CRS in Getis-Ord Gi* hotspot analysis

I have a question about the importance of the chosen CRS in a Getis-Ord Gi* hotspot analysis - I am running a hotspot analysis (using Zone of Indifference spatial relationship) on a quite restricted ...
3
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2answers
43 views

Error to obtain coordinate reference system argument from a raster image in R

I got an error when i wanted to obtain the CRS from stacklayer. I don´t know what could it be. I need some advice or help to obtain it. This is my code. #LOAD RASTER LIBRARY >library(rgdal) >...
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0answers
34 views

Which SQL Server spatial data type to use for UK data in SQL Server?

Which spatial data type should be used for UK data in SQL Server?, i.e. GEOMETRY or GEOGRAPHY? I'm aware of OS National Grid and my understanding is it's an X/Y coordinate system, covering from ...
1
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1answer
37 views

In Layer spatial reference system units

Can I edit the in layer spatial reference system units? I have 2 shape files, they have the same CRS but they have different in layer spatial reference units? I'm new to QGIS and I don't really know ...
8
votes
1answer
163 views

What is my coordinate system preserving?

I'm trying to get a better grasp of coordinate systems, datums, projections etc. I understand that certain systems preserve different things; distance, shape, angles, area. I'm wondering how you can ...
2
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1answer
26 views

Can reference system in Leaflet be changed without disrupting data position?

I have a leaflet map that uses default CRS (EPSG3857) with multiple markers placed on it. Their LatLng are read from JSON file. I want to change map CRS to Simple, keeping markers on exact same screen ...
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0answers
25 views

Raster from Ascii text file doesn't project properly

I created an ascii grid of annual precipitation for CONUS in MATLAB and imported it into Arcmap. The text file can be downloaded here: https://www.dropbox.com/s/0k4x257x597ogij/meanTotalPmm.txt?dl=0 ...
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0answers
50 views

Delete CRS in QGIS

Is there a way of deleting the various CRS's that QGIS lists? We are a Local Authority in England and the only CRS we need is British National Grid, which is set as the default, as well as Lat/Long ...
3
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1answer
50 views

Which CRS would be the most appropriate to georeference a map of Egypt?

I'm trying to georeference a geological map of Egypt from 1981, but I don't know which CRS to chose, either the transformation type nor the resampling method... And once the georeferencing of the map ...
2
votes
1answer
46 views

Assigning CRS using las2las from libLAS?

My las file had a spatial reference of "None." I tried to assign the CRS (in which data were collected) with the following command line: las2las flightline_002.las --a_srs EPSG:32632 lasinfo --no-...
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0answers
23 views

Custom ArcMap 10.3 Projections?

I'm still pretty new to GIS, being a new EIT at a civil engineering firm. Im here to find out if ArcMap has this certain projection. If so, how do I access it? In ArcMap the projection currently says ...
0
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0answers
39 views

Algorithm for converting from projected coordinate system to geographic one using Helmert transformation

I have a data in projected coordinates system and I need to convert them to WGS84. I know the parameters of position vector transformation and I know the projection details of my projected coordinate ...
2
votes
1answer
34 views

Determining CRS from ASCII file?

It is possible to know the CRS from an ascii file? The information I have about it in the heading of the ascii file is the x and y corners: xllcorner -10,000416206603 yllcorner 34,...
5
votes
2answers
192 views

Since ArcMap Projects data “on the fly” why aren't these data sets aligning?

I have a polygon feature class in NAD_1983_UTM_Zone_13N (Green in map). I projected it to NAD_1927_StatePlane_New_Mexico_East_FIPS_3001 (Pink in map). Why are these not aligning? Does this mean the ...
2
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2answers
2k views

WFS: How to specify input coordinate reference system

Geeoserver allows to specify output CRS by parameter srsName in WFS GetFeature. Is there a way to specify the input CRS? I am displaying layers of different CRSs in my map - all reprojected to EPSG:...
3
votes
1answer
85 views

Same crs, different spatial reference system units, shape files / QGIS

I have two files, same crs but different reference system units and different scale. Long story short, the shp files won't overlap :( I've read some answers to what seems to be the same problem but I ...
1
vote
0answers
57 views

projected coordinate system and transformation

I'm a beginner with GIS and I'm currently working on ArcGIS 10.3. I have two distinct shapfiles : one within the projected coordinate system "NTF_Paris_Lambert_Sud_France" and the second one within "...
0
votes
1answer
286 views

Projection error, geotransform not valid

I am trying to extract data from gridded weather datasets such as GLDAS from pixels in which weather stations are located. I created an ArcGIS shapefile of weather station points. These ...
4
votes
1answer
58 views

Converting from one Transverse Mercator based system to another produces inconsistencies

As a civil engineer, the one semester of survey training we had leaves my knowledge quite lacking in the field of coordinate systems. We're working on a project based in Gabon and we get information ...
2
votes
1answer
31 views

How to set coordinate system for deed calls in COGO?

I am working with deeds that display metes and bounds, but the surveyor did not include the coordinate system used. If I am trying to enter this data into Arcmap using COGO, where in the process of ...
3
votes
1answer
423 views

How do I figure out the length of polyline features in a feature class with a WGS 1984 coordinate system?

I'm trying to figure out lengths of polyline features in a feature class with a WGS 1984 coordinate system. Here's code to list lengths: >>> import arcpy >>> inFc = r"C:\Users\e1b8\...
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2answers
229 views

Defining coordinate reference system with rotation in GeoServer?

I am using GeoServer and have a layer in EPSG:900913 ("Google Mercator"). I need to "rotate" the map around certain point (say, 1500000, 7000000) by certain degree (say, 30 degrees clockwise). How ...
1
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2answers
695 views

ogr: how to use epsg database for RD New projection?

I'm trying to assign this EPSG projection to my newly created shapefiles using ogr. The OGR Projections Tutorial says: ...any geographic coordinate system in the EPSG database can be set by it's ...
2
votes
1answer
47 views

Converting NAD 83 State Plane Maryland Feet Coordinates from lat/long and vice versa using QGIS?

I need to convert a list of lat/lon points (in.csv file) into NAD 83 State Plane Maryland Feet and vice versa. I know it can be done using ArcGIS, but I only have QGIS. I am also quite new to QGIS....
2
votes
1answer
42 views

Create a layer in PyQgis with the same CRS as another

I want to create a layer which use the same CRS as another layer I already have in the project. The idea is to avoid the CRS dialog. I tried the things in this link: How to define layer's CRS and ...
3
votes
2answers
83 views

What kind of projection is this?

Can someone tell me what the projection is in this zone map from NOAA? I am trying to replicate it (or get close) in QGIS.
0
votes
0answers
29 views

How to define the Northern Lambert Conformal Conic CRS?

The dataset I got my hands on uses the the Northern Lambert Conformal Conic CRS? I was not able to find a ESPG number using http://prj2epsg.org/search so I decided to define a custom CRS in R but I ...
2
votes
0answers
75 views

Converting KML coordinates to Leaflet

I am trying to convert a Google Map KML file to a csv, to map the longitude and latitude points on Leaflet. But the coordinates keep mis-projecting and some end up off the land mass. The steps I have ...
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1answer
42 views

Calculation of coordinates

How can I merge some small regions to create big regions? Then how would I be able to calculate the coordinates of these new regions?
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0answers
25 views

SRIDs do not match for the two geometries in oracle spatial

I am trying to resolve where some points from Point Geometry lying outside the Polygon geometry. I want to filter those points which are lying outside the polygon geometry. I am getting error where ...
1
vote
1answer
44 views

QGIS Lat/Long Postcodes Coordinates Being Placed Out At Sea?

I've read plenty of posts on this site regarding coordinate systems but none of them have helped solve this issue. I'm using Ordinance Survey Lat/Long coordinates for postcodes but a small number are ...
1
vote
1answer
46 views

Conversion of projection

I have received a drawing with a type of projection system which I do not recognize. The drawing says that it's LO 19/WGS 84. I would like to convert this to decimal degrees to be able to plot the ...