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
9 views

PROJ4 and Qgis 2.8 - does QGis 2.8 depend on PROJ4

So, yesterday I tried to install basemap for python. Doing that, I (tried) to install the PROj4 (https://trac.osgeo.org/proj/) library. Well, of course that did not work. There were many error ...
0
votes
0answers
7 views

Do projections matter for zonal stat/isectpolyrst?

I have a gridded product (at 5 arc-minute resolution) and I have to summarize the raster cell values that are contained in another polygon layer. The raster product doesn't have a spatial reference ...
0
votes
0answers
22 views

Raster displaying in ArcGIS

Can anyone please explain this to me? I need the image to be displayed right in any case as I will be using it in different programs. When I open this raster image in an existing ArcGIS map it ...
1
vote
0answers
31 views

Raster overlay with different projection in Google Maps

I have a map created with Google Maps. I want to overlay over some data I am downloading dynamically, covering the whole world. That data is a matrix as follows: 1024 values for the longitude ...
0
votes
0answers
10 views

Misaligned layers unknown projection [duplicate]

I have two datasets for Rio de Janeiro, Brazil that come from the same original dataset and are almost exactly the same. However, one has been projected into an unknown projection. Both were at some ...
1
vote
1answer
164 views

Tiled raster image to be placed in an OSM/ Leaflet.js map

I have a mapoverlay in a custom projection which I need to add as a layer to an Openstreet map within a website. Since I was not able to change the projection earlier, I decided to manipulate the ...
2
votes
2answers
33 views

Overlaying Shapefile with projection and raster (without projection but with defined extent) using QGIS?

I'm trying to overlay a shape file into a raster. The raster has no defined projection but it's a global raster with extent 0, -1800 : 3600, 0. I tried "on the fly CRS" transformation and followed the ...
2
votes
2answers
28 views

MMQGIS:Create:Hub Distance: Output shapefile in wrong coordinate system

I have a QGIS-project that is completely in EPSG:31467 - DHDN / Gauss-Kruger zone 3. It consists of random points (camera traps) surrounded by a polygon (forest edge). I already converted the polygon ...
0
votes
0answers
13 views

UTM ED 50 transformation to WGS84

I have a set of navigation shot points (pre 1975) with coordinates that are based on a UTM ED50 zone 33 projection and I need to transform these to WGS84. My procedure has been to load the excel fine ...
2
votes
3answers
68 views

Plotting Netcdf data. How to get right projection?

Maybe it's very easy for someone to fix, but I'a a new one in R, so I really need help. I/m trying to plot data containing lat, lon and variable (nmf2). The grid isn't a regular one, so there are some ...
1
vote
1answer
29 views

Guessing unknown projection of Webapp

I have a series of points around the greater london area (may be also around 100-200kms away from it) like those here in the format Lon, Lat: 43032.1,32681 95816.5,34473.8 15439.3,-13987 The ...
0
votes
1answer
17 views

Ogr2ogr trying to import and convert shapefile to EPSG:3857

I'm attempting to import a shapefile (along with .prj file) to MySQL using Ogr2ogr and using the t_srs option set to EPSG:3857 (the default for Leaflet and Google Maps) but I'm getting odd results, ...
1
vote
1answer
441 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 ...
1
vote
1answer
170 views

How to Buffer data in a Geographic coordinate system?

I am having an issue with buffer. My data is in Geographic coordinate system. I am trying to do a buffer of 600m and i am finding different results for each case, have tried thse so far: Map in web ...
0
votes
0answers
19 views

How to set projection parameters in ArcGIS?

I would like to open .hdf satellite data(FY-3 from China) in ArcGIS, but there is unknown projection info in it. The extent of hdf is : top: 0 right:1383 bottom:-586 left:0 And the projection ...
1
vote
1answer
138 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 ...
0
votes
0answers
21 views

Polygon Shifting in WGS 84

I'm troubleshooting some discrepancies between intersection results in State Plane and WGS 84. The intersect was ran when both the polygons and points were same PCS ...
1
vote
1answer
49 views

How to add a lat/lon grid to a map using azimuthal projection?

I have a north azimuthal projection, equal areas. I want to create a map from it (in QGIS) and display a grid on it for better orientation. Thats how it looks like: Why doe my degrees have so ...
1
vote
0answers
36 views

Which projection should be chosen to model transmission lines across the USA?

I am looking at different options for high voltage power lines in the US. These power lines cross several states. Since in the end the distance is of importance, is the USA Contiguous Equidistant ...
1
vote
1answer
29 views

How do I interpret this proj4string and why doesn't changing units change its resuls?

I'm new to GIS - I have a background in statistics. I have the following proj4string: '+proj=lcc +lat_1=40.66666666666666 +lat_2=41.03333333333333 +lat_0=40.16666666666666 +lon_0=-74 +x_0=300000 ...
1
vote
1answer
39 views

Determine projection of a shapefile

Is there anyway to determine projection of a shape file which doesn't have .prj file? I am trying to re-project this shape file to another projection, I know that it is Lat long data. I could manage ...
2
votes
1answer
60 views

World map different projection

I want to display something on a world map. I have these shapefiles http://thematicmapping.org/downloads/world_borders.php I want my map to look something like this: or I am using QGis. Is ...
1
vote
2answers
692 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
108 views

QGIS: How to add a second polygon that is exactly 5km larger in all directions?

Given is a map with an airport. Within a distance of 5km around the runway there is a so called no fly zone for drones (in Switzerland). I want to show this zone in a map. What I would like to do is ...
11
votes
5answers
586 views

Appropriate map projection for the Pacific Ocean

I've found this map that shows the Pacific Ocean from http://www.transpacificproject.com: I'd like to produce a similar map, for the same region of the earth and I'd like to use the same projection ...
0
votes
1answer
172 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
votes
0answers
20 views

Overlay polygons on raster in different projections

I'm overlaying polygons on a raster to get the average value inside the polygon (using SAGA->Shapes-Grid->Add grid values to shapes in the QGIS Processing Toolbox), using a geographic and a ...
0
votes
0answers
34 views

Project Raster Data Loss - 2 Billion People

I am using the SEDAC/CIESIN raster data for population counts. This data is in WGS1984, and I want to project this data to a Fuller projection. After running through "Project Raster" in ArcMap 10.1, ...
0
votes
0answers
22 views

Projection issue in gwp-openlayers

We are trying to display wms laying that uses EPSP 4326 using gwt-openlayers. Here is a sample of its url: ...
2
votes
2answers
465 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? ...
1
vote
1answer
85 views

Different projections in the same shapefile

I was just wondering if it was possible to change the projection of only certain objects in a shapefile, while the others remain the same. I have to insert points onto a map, and some of them are in a ...
3
votes
2answers
84 views

How to load projection along with raster in R?

Why the operation myraster = raster("test.asc") does not load the associated projection file test.prj located in the same directory as test.asc? Does raster() need a specific argument? It seems ...
0
votes
2answers
59 views

US map shape distorted in QGIS

I am very new to QGIS and mapping. I am trying to load a US state map shapefile in QGIS. But the problem is it does not look like another US state map available on the internet. The upper part looks ...
2
votes
1answer
448 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
30 views

Surface Volume 3D Analyst tools

I'm using Surface Volume tool (ArcGIS 10.3) to calculate volume of air from a valley. I delimited my DEM (clip tool) and choose Below as plane reference with 603 m as height. The DEM is projected in ...
0
votes
1answer
182 views

Difference between 2 projections?

I have osm.xml file where projection is defined as follows: Map background-color="grey" srs="&srs900913;" minimum-version="2.0.0"> n settings.xml file projection is also set there as: <!ENTITY ...
0
votes
2answers
196 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
21 views

ArcGIS Layers same coordinates not lining up [duplicate]

I have a large polygon for a borough, and smaller polygons for the local authorities within it (they divide up the borough). When I add the smaller polygon layers, the polygon appears distorted and ...
1
vote
0answers
17 views

Changing Area Output - PUMAS

I currently have shapefile of US PUMAS and another feature shape file (call it feature X). I am using arcpy to project both of these files to the following projection coordinate system (using ...
2
votes
0answers
25 views

Stretching of geometry when rasterizing vector data on Google Maps

I'll start with a quick backstory on what I am trying to achieve. I'm working on an offline Android GIS tool and people are throwing giant datasets at it. It converts these into Google features (V2) ...
0
votes
1answer
40 views

How to create buffer around point having projection 4326

I am trying to create buffer (in meters) around point(long lat alt) which is in projection 4326 with below code. But it is not giving expected output. SELECT ...
0
votes
1answer
32 views

Generate tiles with stereographic projection

I am developing a web application that shows some information to the user on a map. The application is not connected to the internet, so for the first protoype I generated some map tiles using ...
0
votes
2answers
557 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: ...
1
vote
2answers
62 views

GDAL - Warping raster to new domain/resolution/projection causes data loss

I am attempting to warp a GTiff from a lat/lon projection to a higher (~2x) resolution Polar Stereographic grid. In the output GTiff any cells north of 64 deg lat become NaN instead of their actual ...
2
votes
1answer
33 views

Georeferencing uneven/irregularly gridded rasters

I'm trying to take a set of NetCDFs and turn them into georeferenced datasets using GDAL. However, the only Geospatial data is a set of 2-D lat/lon arrays. The projection type is not lat/lon. THe ...
6
votes
1answer
505 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 ...
2
votes
1answer
23 views

Geowebcache alias for custom projections

Is there a way to configure a projection alias in geowebcache? E.g. if I would like to advertise projection EPSG:25833 and EPSG:32633 to the client, while requesting tiles from the backend using ...
0
votes
1answer
40 views

ArcMap ModelBuilder: problem with %name% variable when used in iteration for projection

I have prepared a model which should project all shape files ( currently in MUTM 81) in a folder to MUTM 84. But when I use “%Name%” in output dataset for geodatabase as “D:\Soil ...
2
votes
2answers
5k views

How to create custom coordinate system in ArcGIS Desktop?

I have a series of control points with xy coordinates in both NAD83 UTM and in a local grid. How can I go about creating a new projection file in ArcGIS 10 for the local grid?
0
votes
0answers
34 views

Projecting NAD83 on-the-fly to WGS84 [duplicate]

I have a point feature class in a geodatabase that uses WGS84 as its SRS. A colleage of mine created points in this feature class using an external database containing lat and long values. However, ...