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

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321 views

How do I reproject one raster to match another's in GRASS

I have two raster layers, A and B, which have information about the same location but have different projections and datums. How can I reproject layer A to match the projection and datum of layer B? ...
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2answers
369 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 ...
8
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1answer
172 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 ...
7
votes
1answer
110 views

What are the pros and cons of forcing square pixels on reprojection?

I am using Erdas Imagine 2014 to reproject 4-band raster data from GRS 1980 NAD83 Lambert Conformal Conic (ft) to UTM GRS 1980 NAD83 North UTM Zone 11 (m). Unlike ArcGIS, Erdas provides the option to ...
5
votes
1answer
414 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
1answer
207 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 ...
2
votes
1answer
24 views

Applying distance/area dependent procedures in geographic coordinates over large areas?

I'm currently doing some niche modelling with data in geographic coordinates spanning all of Latin America. I am using R for my analysis. Some of the tasks I have to perform are area/distance ...
2
votes
1answer
142 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 ...
2
votes
1answer
330 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 ...
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1answer
29 views

Unable to save to in Geojson format with the correct projection

I have a shape file (Polygon) in Qgis that I wish to save in Geojson in order to display it with the mapbox javascript api. Original projection is in POSGAR 97 My issue is that it does not reproject ...
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1answer
53 views

How do I convert Geo-Coordinates to Pixel-Coordinates on a Map?

I have an image file that is a Robinson Projection Map of the world. I have a list of geo-coordinates. I would like to find the pixel-coordinates on the map that correspond to my the geo-coordinates I ...
1
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1answer
20 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 ...
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1answer
56 views

Why are some layers saved with custom CRS while others use the appropriate EPSG code?

I have a number of .shp's that I have converted from EPSG 4148 to CPNO27. Some have come out perfectly and others revert to EPSG 1000007. I have checked and the only difference between the two is the ...
1
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1answer
80 views

Lambert Conformal Conic Projection Inverse Transform after Fitting Ellipse to Noisy LLA Data

I'm using Python and Basemaps to convert some Lat Lon data to the LCC projection and back again. Since it is noisy data representing the footprint of a satellite, I am filtering it and fitting an ...
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1answer
84 views

How to reproject from Clarke_1880_RGS_Lambert_Conformal_Conic to ETRS_1989_LAEA?

I am unable to reproject Marseille shapefiles from Clarke 1880 RGS_Lambert_Conformal_Conic to ETRS_1989_LAEA. I know that Clarke is a geographic coordinate system and it has no datum. I have tried ...
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vote
1answer
117 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 ...
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1answer
62 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
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1answer
75 views

Show map using esri leaflet, with 4326 spatial reference

I have this MapServer http://geoservices.big.go.id/arcgis/rest/services/RBI/Rupabumi/MapServer It turns out it uses 4326 spatial reference. I want to present it using leaflet, my code so far: ...
0
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1answer
30 views

Shorcut to apply selected shapefile projection to the data frame in arc gis

What is the shortcut to apply selected shapefile or the newly added data's projection to the data frame in arc gis, well not the traditional way of Dataframe--->Properties--->CS system "This could be ...
0
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1answer
67 views

Adjusting Z Units on a DEM

I am learning how to use ArcHydro and attempting to change the Z Units because I get a warning message saying the Spatial Reference Doesn't Match. The DEM was in Meters, and I adjusted the Z Unit to ...
0
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1answer
75 views

GDAL - projection from pixels to geo coordinates

I am using GDAL library in C++. On my dataset, I have obtained geo transform with GetGeoTransform to GT array (GCP is NULL). Than I use this values for this equation (Source): Xgeo = GT(0) + ...
0
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1answer
187 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 ...
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1answer
239 views

My wms vector data overlay on openlayer vmap work fine but on osm img is not rendering

i am try to overlay my India roads vector over an openlayer (http://vmap0.tiles.osgeo.org/wms/vmap0) vmap work fine.but i want to do the sam task over osm(open street map), i am trying many different ...
0
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0answers
101 views

Lambert conformal conic projection - Europa

I am trying to calculate map of Europa in Lambert projection. I am using formula from wikipedia (Lambert wiki), but calculation is verřy slow with comparison to Mercator. I know, there are sin, cos, ...
0
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0answers
95 views

Doubt in Field Calculator

I am working in an project.I have a point Shapefile its projection is NAD83(HARN)Pennslyvaniasouth(ftUS)*EPSG3365* when I measure its distance(between two points) it gives me the answer in feet .yes ...
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0answers
306 views

openlayersplugin qgis 2.0.1

I have installed qgis 2.0.1, great thing... but.. open layerplugin doesn´t work proper. When I try to load two different open layers I get the answer "could not draw google satellite because:" Also ...
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0answers
125 views

why readOGR() is not reading projection information from .spj - r

0 down vote favorite I successfully import a polygon shapefile with readOGR, however the information in the .prj file is not being imported. test class : SpatialPolygonsDataFrame nfeatures : 19407 ...
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0answers
42 views

matching open layers plugin Google earth to my data

I'm novice to the GIS and am trying to figure out how to keep my datapoints matching to the same projection on Google Earth satellite that I downloaded through the Open Layers Plugin. My data is in a ...
0
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0answers
277 views

ArcGIS / ArcMap problem with tiff file and projection

I have a raster in ArcMap . The projection is WGS 1984 UTM 22. When I look the details of the projection I can see that the "scale factor" is 0.9996 When I save this raster in a in tif file and the ...
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0answers
71 views

How to use projection of a shapefile in order to have a better view in OpenGL

As you see here, this is the code that I have used to extract vertices of ESRI shapefiles in order to show them with OpenGL. I have also uploaded my project here, if you want to give it a try and see ...
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279 views

Help me convert this US Lambert Conformal Conic Google Maps Projection to Australia

Following on from this question: Identify what projection this Australian map uses? <- this is the sort of map i want to load in I need help changing the bits necessary in this example of Lambert ...
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0answers
83 views

Sort a collection of points based on proximity using pythagorean (2D) distance

I would like to present a user with a list of points, sorted by proximity to the user's location. Is there any problem with using the pythagorean formula to calculate the two dimensional distance ...
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0answers
63 views

Van der Grinten IV projection. Is it possible and how?

I like the look of the Van der Grinten IV projection with it's two hemispheres and would like to use if for a map of the world. I could only find information on how to use the Van der Grinten I ...
0
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0answers
266 views

How do I redefine the projection of a DEM?

I have a DEM that was exported from AutoCAD civil 3D 2013 but it's in the wrong projection. I'm using an area specific projection that was not provided as an option in CAD DEM export dialog box. I ...
0
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0answers
36 views

Unpredictable cropping and display of projected geodetic layer in QGIS

Here's the setup: QGIS 1.9.0-master, running on Ubuntu 13.04 I have a two layers and with two different Custom CRS defined The basemap image and project use this one: +proj=eqc +lat_ts=0 +lat_0=0 ...
0
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0answers
115 views

Map doesn't show anything in img file (WMS-Mapserver)

Actually in a practical Project we wanted to use OpenLayer and MapServer to display our data using WMS, but We can't find a proper srs or EPSG code. One of the ITC students said, we have to change our ...
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0answers
61 views

Why does ERDAS not like my GDAL output?

I am creating a raster using GDAL and the IMAGINE file doesn't work in ERDAS because it doesn't recognize the projection. Here is the code to generate a sample: from osgeo import gdal projectionWkt ...
0
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0answers
109 views

Changing the projection of the output to my OpenLayers click event handler

I've been playing around with the OpenLayers click event handler example, which you can see here. It tell you the coordinates where you have clicked but I am trying to change this to be in decimal ...
0
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0answers
81 views

Why does a shapfile shift after transformation?

I have a shapefile created in the raster package (ER_14.3_2000_poly). > #read in a raster file > ER_14.3_2000<-raster('E:/Ecoregions Models/Outputs/ER_14.3/ER_14.3_ConsensusMap3.asc') > ...
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0answers
144 views

MapServer Mapfile: Scalebar not displaying correct distances?

Scalebar: SCALEBAR LABEL COLOR 0 0 0 SIZE SMALL END STYLE 0 SIZE 180 8 POSITION lc COLOR 0 0 0 UNITS MILES INTERVALS 2 TRANSPARENT TRUE STATUS EMBED END I didn't even ...
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0answers
68 views

Changing projection does not change map extent

I have a shape file with a UTM projection. I want to save the data to a new shape file with a lat/long projection for a mapping system that only can deal with lat/long projections. I open the UTM ...
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0answers
47 views

How to retrieve PROJECTION value for a map?

I am trying to read the Projection from Geotiff/shape file, using gdal 1.9.0 by the following command in the command line... gdalinfo.exe -proj4 map-path but its retuning empty string for ...
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0answers
131 views

How to find out what projection my data is using?

I have a set of data that I created from gps locations of images. The locations are in decimal. I don't know what projection was used when the data was captured. I used QGIS to display the data with a ...
0
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0answers
78 views

need info on GeoTIFF projection keys

I am a programmer (not a cartographer!!) developing an application which needs to read and write GeoTIFF files. I have a number of questions about those GeoTIFF keys which are related to projections. ...
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0answers
31 views

QGIS: Unable to project raster layers correctly on a Toshiba Tecra 64# Win7

I know how to project a raster, I can do it on other machines. On this particular machine the raster loads but are no where near the correct position as if the datum is on another planet.
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96 views

How to get Earth radius in pixels?

I need Earth radius in pixels for use in Mercator projection. Well let's say that our map's height is 1478 pixels and distance between 0 pixel and 1478 pixel is 2.52 degree. Radius is distance from ...
0
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0answers
127 views

I want to change EPSG:4326 to EPSG:900913 using C# for a set of uploaded shapefiles

I have written some code (using help from these pages) that uploads a directory full of shapefiles to a geoserver using C#. The uploaded shapefiles are set to EPSG:4326 however I would like them to be ...
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0answers
111 views

How to join edge of International Date Line in world file?

I am currently using world file (http://www.ngdc.noaa.gov/mgg/shorelines/gshhs.html) for international boundary information. Now I have difficulty with map projection that the map ends with ...
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0answers
53 views

export WebMap in a different projection than the WebApi

I am quite new to the Flex WebApi world. I am using the Flex WebApi and have set up map templates to print maps out to my own template as a PDF. In my template I have the Map grid set. When I eport ...
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76 views

Changing projection of base layer

Normally, we change projection of vector data for displaying it over a Google base map. Is it possible to change the projection of base image tiles map? If yes, how we can do that? Any reference or ...