A map projection is any method of representing the surface of a sphere or other three-dimensional body on a plane

learn more… | top users | synonyms (1)

0
votes
0answers
6 views

Is it possible to rotate the geographic projection in QGIS?

I'm trying to create a Qgis plugin that can rotate a raster layer in the canvas so that the north is pointing at another direction. Unlike the thread below, I'm open to defining a custom projection. ...
1
vote
1answer
14 views

XY data --> NAD_1983_2011_California_Teale_Albers always fails?

In ArcGIS 10.2, I am importing XY (point) data from excel, and have been having trouble projecting it into the following Projected Coordinate System: NAD_1983_2011_California_Teale_Albers -- NAD ...
1
vote
0answers
23 views

image rectification with Mercator projection

I have written an image rectification function which allows a user to select 2 points on an image and 2 points on a map. The function will then rectify the image so it is translated, scaled and ...
1
vote
1answer
23 views

Projecting INEGI shapefiles from Mexico

I have two INEGI files from Mexico (1990 and 2010) that I want to use the same projection. The 2010 file works fine (see below) and I would like the 1990 file to match the 2010 one. The shapefiles are ...
2
votes
1answer
32 views

Projection mismatch when plotting precipitation with ggplot

I'm trying to plot accumulated precipitation in Brazil for a given period, see code below: Load packages library(raincpc) library(SDMTools) library(raster) library(ggplot2) library(rgdal) ...
2
votes
1answer
319 views

OpenLayers and custom Proj4 Projection

ok so I'm a newbee in using OpenLayers. I try to map some planetary data on my webMap server using OpenLayers. I defined a proj4 projection as follow: Proj4js.defs["MYDATUM"] = "+proj=longlat ...
0
votes
0answers
17 views

Custom projection with mapnik

I would like to superimpose openstreetmap data over a raster image, using mapnik. My problem is that this image is not in a projection being defined by a SRS, I have some non-linear algorithm to run ...
3
votes
2answers
48 views

Why orthographic projection has been used in this NatGeo map

I'm wondering why this maps uses orthographic projection, and result is 3 maps to view the whole world, what were the requirments or the reasons to choose this projection (why not mercator ) ? this ...
0
votes
0answers
31 views

What projected coordinate system to use for whole of USA? [duplicate]

I need to determine a projected coordinate system for a wide area that exceeds more than one zone? For Example: If I want to give US a UTM projection which zone will be represent the whole US? ...
0
votes
2answers
99 views

Projection problem? — OpenLayers, Drupal, and MapBox

I've installed OpenLayers in Drupal 7 and created a view that pulls geofield data for a "Geography" vocabulary (states, tribes, and U.S. jurisdictions) and shows points on a map that I'm storing on ...
0
votes
1answer
28 views

Drawn figure looks stretched

I have written some code which offset a certain latitude and longitude with a distance in centimeters. What I am trying to do is based on a coordinate and a vector create two new points along the line ...
0
votes
0answers
22 views

Euclidean Distance Function performed on unprojected data

I am looking to perform a simple multi-criteria analysis on a data set comprised of two criterion: occurence of wildfires and road accessibility. First, the project CRS was enabled with "on the fly" ...
0
votes
2answers
30 views

OpenLayers + Geoserver problem with wfs projection

In geoserver i have a layer in EPSG:26191. In OpenLayers i add it on map as WFS: markerLayer = new OpenLayers.Layer.Vector('Markers',{ strategies: [new OpenLayers.Strategy.Fixed()], ...
0
votes
1answer
67 views

QGIS to solve projection mystery in Postgresql

I downloaded some data from local agency. Per QGIS 2.2, I defined the projection to 'EPSG:3587 - NAD83(NSRS2007) / Michigan Central' in postgresql (maybe ArcMap). Data is in Postgresql 9.3. I am ...
1
vote
2answers
52 views

Wherer is wrong with transforming a WGS84 [lon,lat] point onto google maps

I want to convert a longitude latitude point in WGS84 coordinate system to Google Maps(not google earth) coordinate, But when I put the converted point on google map, it always has a roughly 10km ...
0
votes
1answer
40 views

which Coordinate system should I use for 3D analysis?

I am creating 3D surface below the earth's surface using ArcGIS and then I need to find distances to the plane from the surface. Which coordinate system shall I use? 3D interfaces like IProximity3D ...
1
vote
0answers
36 views

Why can't I reproject from HARN State Plane Ft Intl to State Plane Ft?

I'm attempting to reproject a feature class that is: NAD_1983_HARN_StatePlane_Oregon_North_FIPS_3601_Feet_Intl to our standard, which is: NAD_1983_StatePlane_Oregon_North_FIPS_3601_Feet When I ...
8
votes
0answers
522 views

How to define Winkel Tripel in proj 4.8.0?

I have QGIS with proj 4.8.0 installed. I'd like to add Winkel Tripel projection which seems to be defined as +proj=wintri But that definition string does not work. Is this a bug in my proj version, ...
1
vote
2answers
30 views

Projection for polygon intersection confined into one hemisphere?

I have polygons where each vertex is a (lon,lat) geographic coordinate. I want to find out if they intersect or contain each other. The polygons are guaranteed to never exceed a hemisphere (so they'll ...
4
votes
1answer
74 views

What's the correct way to reproject a population raster?

I'm working with a population raster that is in the WGS84 coordinate system, and I want to get it into a projected coordinate system (Albers Equal Area), using ArcGIS 10.1. According to the metadata, ...
2
votes
1answer
122 views

using PostGIS to calculate distance of a route over a large area

I'm new to PostGIS and looking to measure the distance of the Pacific Crest Trail which spans western North America from Canada to Mexico. I have a data set containing the lat lon and dates from GPX ...
1
vote
0answers
25 views

Geodjango transform introduces large errors

Apologies for the possibly naive question. I'm trying to understand how Geodjango (running on PostGIS) deals with coordinate transformations, and am experiencing some unusual behaviour. Let's say I ...
1
vote
1answer
18 views

Geoserver projection recognize problem

I'm publishing shape files in geoserver through curl,my problem is that geoserver didn't recognizing the projection which is in ESRI WKT format(layer was publishing).I searched for this problem i ...
0
votes
0answers
33 views

Fixing Mapinfo export to Google Earth projection which is slightly off?

I have around 20 layers of data (points and polylines) in Mapinfo TAB files which I need to export to KML files, however the projection is slightly out. I have tried various different projection ...
0
votes
3answers
52 views

Problem with Geometry SRID in PostGIS

i ceated my table (borne) in PostGIS id_borne serial NOT NULL, num_borne character varying, shape_borne geometry and i changed the SRID of my table with succes using select ...
18
votes
8answers
15k views

How do I convert State Plane coordinates to latitude-longitude?

Given a specific state plane coordinate system (whether NAD27 or NAD83), are there any resources to convert to latitude-longitude?
1
vote
1answer
221 views

Is there a standard projection for Sub-Saharan Africa?

With the help of d3.js, TopoJSON, and data from Glottolog I have made this map of Bantu languages that exist in Sub-Saharan Africa. I've used the standard Mercator projection so far. I know that ...
9
votes
1answer
159 views

Mercator bias plot in Leaflet

I was inspired by this wikipedia image from the mercator projections page to hack around with leaflet. The idea was to interactively have your cursor move a continent and that it would be corrected ...
1
vote
1answer
44 views

Accurate local map projections

Is there a map projection that can accurately represent reality at a local area, i.e. when transforming the map could I choose an area that I care about accuracy and allow distortions elsewhere? Like ...
1
vote
2answers
37 views

OpenStreetMap Tile Server with Custom Projection Systems

I am trying to install the OSM tile server on a local machine with a custom projection system like epsg:3573. For the server installation I followed this tutorial ...
1
vote
0answers
51 views

MySQL+GDal+MapServer+OpenLayers WebMercator problem

I have a problem/question what is the most efficiant way to go from WGS84 (epsg:4326) to webmercator. Outline of the structure right now: MySQL Database: with point Latitude/Lontiude Data [~200 ...
1
vote
1answer
37 views

Correcting coordinates of CAD drawing imported into ArcGIS?

I am having some issues with some CAD drawings that I have imported to ArcGIS. I have a number of CAD drawings where by the features within the drawing have an error in their coordinates. For example, ...
1
vote
1answer
318 views

How to re-project the EASE (Equal Area Scalable Earth) grid with a ~25 km cylindrical projection to WGS84 0.25 degree?

I have nc files ,here is one file https://echange-fichiers.inra.fr/get?k=LUfqiyO1Dl7az5bihnS. from the metadata ,the projection is cylindrical and the resolution is 25 km: ...
3
votes
2answers
42 views

Choosing projection to use for Least-Cost Path analysis at continental scale?

I am trying to find least cost paths from the southern USA to the Great Lakes region (for example). My resistance layers are currently in an equal area projection but I'm wondering if I should convert ...
0
votes
2answers
384 views

OpenLayers WMS - TypeError: this.resolutions is undefined

I'm trying to setup a map with WMS and WFS Layers by using Geoserver. However, when I'm combining WFS and WMS (with some Google basemaps) together in one map I got following error in Firebug: ...
5
votes
1answer
400 views

Determining Natural Origin for a GeoTIFF file (Lambert Conic)

I am trying to display an existing GeoTIFF file (from the FAA WAC set) in an application that requires the GeoTIFF NaturalOriginLongitude tag (FalconView 5.1.1). There are some older files in that set ...
3
votes
2answers
190 views

QGIS DXF file projection match

I need to use this file on a map but I am not able to match the projection with the others I have, primarily data downloaded from OSM (city of Boston). I read many articles, I have repeatedly tried to ...
1
vote
2answers
346 views

GDAL/proj4 equirectangular projection coordinate system units assumed by OGRSpatialReference and GDALDataset::GetGeoTransform()?

How do I configure my OGRSpatialReference object to specify an equirectangular projection system http://en.wikipedia.org/wiki/Equirectangular_projection where the affine geo-transform matrix (provided ...
0
votes
1answer
169 views

Projection to use with satellite image from Google Maps / Earth

I'm very new to anything concerning GIS so please forgive me if this question has been asked before, but I assure you, I've been trying to find an answer for quite some time now. Of course it is ...
0
votes
0answers
31 views

Conversion problem of projection of MODIS LAI from sinusoidal to geographic

I am trying to change MODIS data's (LAI) sinusoidal projection to geographic. Actually I did it. But when I reproject it by ERDAS, the output LAI raster moved about 10 km to west side of actual shape ...
1
vote
0answers
24 views

EPSG1612 transformation [closed]

I have survey data for contacts listed as eastings and northings - I need to overlay this onto PNG files but the location is quite far north - How do I apply EPSG 1612 transformation to the UTM Zone ...
29
votes
11answers
8k views

Identifying Coordinate System of Shapefile when Unknown?

I have a Shapefile but its coordinate system is Unknown, and there is no *.prj file. How I can identify it now? Are there any tools that could help?
2
votes
1answer
107 views

Wrong projection high quality shapefile for the coastline of Helsinki region (Finland)

I did some spatial interpolations in R and I need a support for those. Looking for shapefiles online the best I could find was and it looks really horrible, the same area in ggplot looks like . I ...
0
votes
1answer
25 views

Projections when using google maps and rest service on openlayers

I am trying to use a rest service on an openlayers map that has 2 google maps layers. The google map layer is set to it's own custom projection (which I had to code into the library by hand, but I ...
0
votes
1answer
52 views

projection conversion from mercator to google maps format

Is this spTransform(Finland3, CRS("+proj=longlat +ellps=WGS84 +no_defs+ellps=WGS84 +towgs84=0,0,0 ")) the right way to project a shapefile with this projection coord. ref. : +proj=merc +lon_0=0 ...
0
votes
0answers
40 views

Creating a custom Lambert Conformal Conic projection in ArcGIS 10.1 and/or 10.2.2

referring to the table below, I am trying to use the values on the left from another program that uses different terms for the parameters of a custom projection. I just wanted to make sure that ...
1
vote
1answer
108 views

Trying to set NAD 1983 EPSG 102631 in QGIS

I was able to find the right coordinate system online NAD 1983 Alaska But now I don't know what to do. I can't find the coordinate system on QGIS. When I choose the one I think is correct it warps ...
2
votes
3answers
111 views

How to use PROJ4 to reproject a file

Unfortunately, GDAL does not support a particular projection I am trying to achieve (the ob_tran rotated pole projection), so I am trying to use PROJ4 to convert a geotiff file to the projection I ...
0
votes
2answers
46 views

How to set a coordinate transformation GRID

Does anyone know how to set a coordinate transformation in qgis so I can measure the distances in meters or kilometers? If anyone has a clue, would be just great. Thanks!
3
votes
1answer
200 views

1944 Cyprus Grid coordinate data projection problem in MapInfo

I have coordinate data from the 1944 British Army General Staff, Geographical Section (GSGS) Cyprus map which was cast on the Cassini projection, but was referenced to the Clarke 1880 ellipsoid where ...