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
601 views

How to set right coordinate system?

I have shapefile (points) which I got from adding xy data in ArcMap from Excel table. I had Latitude/Longitude data. It is area of northern Australia. For example (5 points): Longitude 136.882 ...
2
votes
1answer
91 views

Populate planet with data

i have a game that described a planet and is a sphere. on the client side, the world is separated to tiles (images) and i mapped it follow by this and this, so now when the user is zooming / dragging ...
2
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1answer
59 views

How do I set the projection and coordinate system for a TIFF file?

I have a topographic map of California (obtained from CAL-Atlas) as a TIFF file. I tried importing it into QGis, but it displays the map using a pixel based coordinate system rather than ...
2
votes
1answer
34 views

App using latitude and longitude, should decimal degrees be a separate selection from metric?

So silly question to some I suspect. I am coding a mobile app that displays coordinates in parts of the interface. We currently have an option to toggle between Imperial and Metric. But I am unsure if ...
2
votes
3answers
189 views

How to calculate Polyline length in kilometres without changing projection from WGS84 (using ArcObjects)?

I have Road (polyline) feature class and I wish to find those roads whose length are greater than 500 kilometre. The feature class projection is in GCS_WGS_1984 and I do not want to change the ...
2
votes
1answer
64 views

QGIS layers don't overlay after trying 'enable on the fly' and CRS settings

I know there are already many questions about this topic, but none of the answers helped me so far. I have two layers I want to overlay in QGIS. One of them is an Excell file with the coordinates of ...
2
votes
1answer
89 views

Problem converting coordinates

I'm trying to convert punctual values from lat/long to EPSG:6372, a projection for Mexico, defined by the Instituto Nacional de Estadística y Geografía (INEGI). I found a converter online but somehow ...
2
votes
1answer
414 views

Canvas Units to Degrees, Minutes, Seconds

I am using the WGS 84/UTM coordinate sysytem. When I go to > Project Properties / General / Canvas Units to Degrees, Minutes, Seconds my coordinates are wrong. I am using QGIS 2.0.1
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1answer
21 views

IL East 1201 coordinate system

What is the difference between NAD CORS96 (Illinois East 1201) and the "normal NAD1983? We have data that was GPS'ed in CORS96, but data was imported into ArcMap using the "normal" NAD1983? What ...
2
votes
1answer
118 views

Batch tool to identify coordinate system in dwg files

I am trying to ingest 1000's of DWG files into ArcGis. Some of them are clearly georeferenced (that is, if I view them in ArcMap I can see that there are in the right place relative to my other GIS ...
2
votes
1answer
116 views

What is the range of numbers for coordinates in geographical coordinate systems

Up to now I thought the range of values in the geographic coordinate systems was: Northing : between -90 to +90 Easting : between -180 to +180 I have set the coordinate system of my dataframe in ...
2
votes
2answers
315 views

finding the correct transformation (from EPSG:31300 to EPSG:4326) or how to store two srid in one table

I have a very specific problem. I have data crossing two coordinate-systems, more specifically: the Netherlands and Belgium. Previously the data was stored in one table in Oracle, using the RD ...
2
votes
1answer
271 views

extracting data from rasters using shapefile boundaries in r

I have a raster.stack of 8 environmental variables and a shapefile of Ecoregions for the southern U.S. files<-list.files(path='E:/Ecoregions Models/Border Bioclim/',pattern='asc', ...
2
votes
1answer
71 views

Coordinate System correctly renders both decimal Long/Lat and some number in the billions

I am new to ArcObjects and I have been creating an application which will (among other things) be reading data in from a sister program and plotting it on the map.I have found out that I can enter the ...
2
votes
1answer
150 views

Calculating points in the USDA's Cropland Data Layer coordinate system

I need to integrate against the USDA's cropland data layer. They've got a demo and some API docs. The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537): ...
2
votes
1answer
54 views

why can I only define 6 custom CRS?

Using Q GIS 1.8.0 - I am trying to create several custom CRS definitions for the purpose of rectifying several split areas of a census shapefile. In the "Custom Coordinate Reference System Definition" ...
2
votes
1answer
844 views

QPJ files on ESRI software

We have some GIS data, which was converted from AutoCAD dwg to TAB using mapinfo, then converted to shapefiles as that's what we are required to create. Editing the data fields was done in the shape ...
2
votes
1answer
128 views

Setting coordinate systems in QGIS: “transform error caught”

I'm learning how to use QGIS (v 1.8.0 "Lisboa") on Mac OS 10.6.8. My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
2
votes
1answer
300 views

Is it possible to convert data from WGS84 to Bessel1841?

When we convert data from bessel1841 to WGS84, parameter setting must be used because it is impossible automatic convert on QGIS. Reference: Converting shp file from bessel1841 to WGS84 Is it ...
2
votes
1answer
97 views

How to get a list of all projections that are currently available in QGIS via the PyQGIS-API

i'm building a QGIS-Plugin and i want the user to choose a CRS out of a combobox in which the coordinates he would enter into some textfields are represented, so these can be converted into another ...
2
votes
1answer
209 views

Problems with NAD27 projection in QGIS

I have some data that is in NAD27, but I am having a hard time displaying it in QGIS. I think that the problem is with the CRS. I cannot seem to find the correct NAD27 option. The closest one seems ...
2
votes
1answer
114 views

What are the geometric principles and GIS techniques that I can use to generate a postcode coverage of my city at street scales?

Postal codes of Brazil and another countries are oriented to distribution logistics, and improvement of reliability in writing the postal addresses; but without much concern for the spatial ...
2
votes
2answers
152 views

Coordinate system of a raster file to be introduced for transformation

I am working on raster data using GDAL. When I extract coordinate system information of the files I got this: PROJCS["Geostationary_Satellite", GEOGCS["GCS_Unknown datum based upon the custom ...
2
votes
1answer
74 views

Latitude and Longitudes are replaced with zeros when importing excel 2007 worksheet into personal geodatabase

I am trying to import an Excel 2007 data set into a personal geodatabase so I can convert coordinate systems. The data set includes point locations in Decimal Degrees. When I import the Excel ...
2
votes
3answers
2k views

Problem with spatial reference system / shapefile projection

I am new to using QGIS and having some problems getting some shapefiles to project correctly. I am using publicly available shapefiles for New York City municipal boundaries found here: ...
2
votes
1answer
371 views

coordinates in dbf file wrong

I am new to ArcGis, so please bare with me :D . I converted a polygon in an mdx file I have to a shape file, then converted its vertices to points, then used "add X Y feature" and choosed coordinates ...
2
votes
1answer
107 views

Does QGIS support MT83F

Does QGIS support NAD83 Montana State Plane Zone, US Foot? I have vector data in a CSV file that I would like to display, but the coordinate system is MT83F. I don't see a matching CRS. Is there a ...
2
votes
2answers
451 views

Determining correct Coordinate System DHDN Bessel 1841

I am working on a data set and coordinates are supposed to be in DHDN Bessel 1841. Have a look here: https://www.pegelonline.wsv.de/gast/stammdaten?pegelnr=2330013 I created a shapefile with the ...
2
votes
1answer
295 views

Two rasters created from the same polygon have different extents?

My problem is that i am trying to export some rasters to Rockworks so that i can create a sand layer from them. Rockworks requires the grid files i use to have the exact same XY co-ordinates. So i ...
2
votes
1answer
14 views

Is it possible to get coordinate system name from SQL Server geometry type?

I need to get the name of the coordinate system of a geometry type field in SQL Server 2008 R2 (for example NAD_1983_UTM_Zone_14N or GCS_WGS_1984 or other). Is this possible?
2
votes
1answer
31 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 ...
2
votes
1answer
32 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 ...
2
votes
1answer
69 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
43 views

How can I carry out a reliable coordinate transformation for point data?

I have ArcGIS 10.0 with ArcGIS Server (AGS) 10.0. Due to a known bug in the AGS geometry service we cannot carry out coordinate transformations with AGS 10.0. Our Internet client therefore does not ...
2
votes
1answer
94 views

What do different realizations of the same datum have in common?

Firstly, am I correct in assuming that the process of determining the shape and the size of the spheroid is independent from the process of determining the origin and the orientation? For example, ...
2
votes
1answer
95 views

Viewshed analysis and coordinate systems ArcGIS 10.1

I am trying to run a viewshed analysis and I've downloaded DEM data from the UK ordnance survey (Landform-panorama). Since the data is in ASCII format I have created a seamless raster mosaic (and used ...
2
votes
1answer
89 views

Change coordinate system of a WMS service

I have a WMS service that is projected to UTM/SAD-69. My workspace is in WGS-84 with no projection. I want to change the coordinate system of my WMS service. Is it possible in ArcMap 10.0? The wms ...
2
votes
1answer
116 views

Waterman Projection in ArcMap

Anyone have any idea how to create (or where to find) the Waterman "Butterfly" projection in ArcMap?
2
votes
2answers
59 views

How to set my own CRS in QGIS

I want to transform WGS to MRT (GCS for Malaysia) using QGIS. Is "save as" to a new CRS the correct method? With ArcGIS, I can create transformation method to do transformation but I'm not sure in ...
2
votes
1answer
88 views

Why does same image in two ArcGIS ArcMap configurations show different extent numbers?

I would like to get hear from you about the situation I am seeing here. What It got my eye was that when I download an ASTER from Reverb/ Echo from USGS website. At work, I load my ASTER file to my ...
2
votes
2answers
131 views

Older British Geological Survey geology maps of Kenya; need complete projection information

I have several geologic maps of Kenya produced by the BGS circa 1993. Noted on each map is the following: Projection:-Transverse Mercator Spheriod:-Clarke 1880 (modified) That's great, but that ...
2
votes
1answer
105 views

Caching aerials in a different coordinate system

I have a strange problem to deal with caching of the aerials. All of our Aerials are stored in SDE in State Plane WKID-2237 (NAD_1983_StatePlane_Florida_West_FIPS_0902_Feet). But we are planning to ...
2
votes
1answer
64 views

When is a projected length calculated via a pythagorean distance more accurate than an ellipsoidal length?

I'm using spatialite 3.0.1 with the following test data (in EPSG: 4326): Name astext(geometry) ---------- -------------------- Belitsa POINT(23.563 41.947) Malko Tarn POINT(27.533 ...
2
votes
1answer
76 views

Ok to measure and union a projected-on-the-fly shapefile in ArcMap?

I have a dataframe in arcMap 10.0.4 that is of Africa Albers Equal Area Conic PCS. I bring in a census shapefile of WGS 1984 CS and it is projected on the fly. I do 2 things: I use the calculate ...
2
votes
1answer
102 views

How to fix distortions for Baden-Württemberg?

I'm working in an area in Baden-Württemberg, Germany. I loaded some OSM data in QGIS but the map display is distorted. I tried ftools define projection with many different projections but nothing ...
2
votes
1answer
122 views

Need to convert from ISpatialReference to SpatialReference

I am attempting to write a method in C# that will accept as input, an ESRI.ArcGIS.Geometry.ISpatialReference object and convert it to an ESRI.ArcGIS.Client.Geometry.SpatialReference object. I need ...
2
votes
1answer
98 views

Library design: Layer coodinates/origin

I am working on a vector map library where you can add plain image and vector layers to a map. The map itself consists of an infinite coordinate system and each layer is a coordinate system of it's ...
2
votes
1answer
644 views

Convert shapefile in NAD27 from meters to decimal degrees to match xy data?

I have a shapefile of a boundary (polygon) that has the following projection: NAD_1927_UTM_Zone_11N Projection: Transverse_Mercator False_Easting: 500000.00000000 False_Northing: ...
2
votes
1answer
494 views

How to speed up this simple MySQL points in the box query

MySQL doesn't have nearest neighbor search so. So I try to come up with a "distance" that's reasonable so the number of returned query is around 20-200. That way innodb doesn't have to compute ...
2
votes
1answer
378 views

How to create aux.xml file?

after starting to use MOBAC to create offline background maps I found the aux.xml files very useful as QGIS automatically sets the CRS so this would be very useful for my colleagues with smaller GIS ...