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
1answer
37 views

Convert from WGS84 to 2D projection

I have a map in the form of .bil & .hdr using WGS84. I'd like to convert this into another map using a 2D projection while keeping the lat/long information. What I'd really like with this new map ...
0
votes
1answer
48 views

Problem to create composer with open layer plugin in QGIS

Creating layout in composer I am facing a problem of dislocation of shp file and google earth image ( which I am using from "open layer plugin") Version 2.4.0 Chugiak (Mac) In the first image shows ...
1
vote
1answer
40 views

NAD83 2011 AZ central projection

I am having trouble getting GDAL to read a file geodatabase with data projected in NAD83(2011) State Plane Arizona Central FIPS 0202. I have developed the following code: # standard imports import ...
1
vote
1answer
101 views

How to project WGS84 raster in lat/long to WGS84 UTM in ArcMap 10?

I know this is suppose to be simple and I've found similar questions. However when I try to do the same (data management tools > projections and transformations > raster > project) inserting input ...
1
vote
1answer
33 views

Projection change in QGIS after import & export in Grass

I'm working on an application written with Grass command in python and I have a projection problem. First I create a location with belgian lambert 72 (EPSG:31370) in Grass 7.0. After importing all ...
2
votes
1answer
49 views

X and Y after Albers lat and lon transformation

that is probably a very obvious question but it is melting my brain: when transforming lat and lon to [x,y] (for instance using this code https://gist.github.com/RandomEtc/476238) I get the ...
0
votes
1answer
29 views

gdal_translate or gdalwarp to define projection

Which of these is the best approach to define (aka. set) a projection for a tiff? 1) gdal_translate -a_srs EPSG:32182 in.tif out.tif 2) gdalwarp -s_srs EPSG:32182 -t_srs EPSG:32182 in.tif out.tif ...
4
votes
1answer
71 views

If Geographic Coordinates are unprojected coordinates, how can GIS softwares display such unprojected data on a plane?

I have been using ArcGIS and QGIS regularly for about 2 years now, and just recently I was struck by this new thought. If a data set in say, in ArcMap, has been georeferrenced with a Geographic ...
6
votes
1answer
73 views

Lambert conformal conic isn't actually conformal?

Mathematically a conformal map has the property that the Jacobian of the transformation is a scaled version of a rotation matrix. The transformation involved in a spherical Lambert conformal conic ...
0
votes
1answer
60 views

SRID, Shape2SQL and SQL Server 2008r2 query

I'm using Shape2SQL to load the Ordinance Survey's Meridian 2 map into SQL Server 2008r2 (which is working very smoothly and painlessly). According to this page ...
4
votes
1answer
85 views

How to use SRTM Global DEM for Aspect calculation?

I need to derive a raster representing aspect for North America (from STRM data, originally in geographic lat/long). In most projections, true north is only map north along eg the central meridian so ...
0
votes
1answer
61 views

How to get projection data (.prj) of raster image using GDAL/OGR?

I start with a boundary shape-file (think U.S. states) in lat/long that I convert to some projection, and then rasterize the result as a .tif. What I need now are the raster coordinates of the ...
1
vote
0answers
39 views

project hdf file with geospatial_lat and lon in batch process

Is there any way that I can do a batch process in projecting hdf files wherein I could get and include only the geospatial_lat and lon in the batch script since every hdf file have different ...
1
vote
1answer
22 views

Why prj2epsg cannot resolve PostGIS SRText?

In many places I have seen people referring to http://prj2epsg.org (here, here). I have used this service too, however, the service cannot uniquely identify an EPSG code alway. I understand that it ...
1
vote
0answers
36 views

Spherical Mercator - World bounds

What are the correct world bounds in the Spherical Mercator projection (EPSG:3857 and EPSG:900913) In some source I got those bounds see this link in the maxExtent parameter: minx: -20037508.3427892 ...
2
votes
0answers
27 views

Finding centroids for icosahedral gnomonic projection?

I've been trying to create an icosahedral gnomonic projection, like this example by Jason Davies or this one (the Fisher projection). The method that I initially used was using the centroid of each ...
0
votes
1answer
60 views

Difference between WGS_1984_UTM_33N and GCS_WGS_84

What is the difference between: a map that has a projected coordinate system of WGS_1984_UTM_33N, a geographic coordinate system of GCS_WGS_1984, and a datum of D_WGS_1984 a map that has no ...
2
votes
0answers
26 views

Thiessen polygons extend outside of extent of projection

I'm working on a geological project on the past position of continents (in ArcMap 10 Service Pack 5, build 4400). The tool I'm creating in Model Builder uses Create Thiessen Polygons and all input ...
1
vote
0answers
88 views

How does OpenLayers 3 handle coordinates?

Ol3 always uses the flatCoordinates because obviously it needs 2d-coordinates as the screen is only 2-dimensional. But how does OL3 calculate the flat representation? For example if my view’s ...
0
votes
0answers
25 views

ArcGIS Online no spatial reference

My intention is to georeference an image so as to create a Swipe Map in AGOL. First, I add my control points, rectify, then analyze before attempting to share and finally publish in AGOL. The other ...
1
vote
0answers
27 views

set Default projection in postgis table

I've set the SRID 4326 for a table having geometry column, but when i insert a geometry without SRID, i get an error because no SRID specified is interpreted as -1 or 0, so how i can set a default ...
3
votes
1answer
53 views

How to manually add spatial reference information for FEWS rainfall data in ArcMap?

I am trying to match rainfall data from USGS/FEWS to coordinate locations of survey households in Uganda, so I will need to be able to project the rainfall data. So far, I downloaded the dekadal RFE ...
1
vote
0answers
37 views

Zonal geometry output in ArcGIS

Is there a way to specify the coordinate type in Zonal geometry output in ArcGIS? I am trying to perform zonal geometry on a raster and in the resulting output, the XCENTROID and YCENTROID are in ...
1
vote
1answer
132 views

Openlayers 3 WMS custom projection wrong extent

I'm using Openlayers 3 to view a WMS-layer from a Mapserver in EPSG:3006, see the code: Proj4js: Proj4js.defs["EPSG:3006"] = "+proj=utm +zone=33 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m ...
2
votes
3answers
107 views

Best Projection for Getis Ord Gi* Statistic Analysis

I am about to calculate the Getis Ord Gi* statistic for some rasters whose extents are global. In choosing a projection, do I want to preserve distance (e.g. equidistant) to obtain accurate ...
0
votes
0answers
20 views

Multiple Satellite Swatch processing for 1 years worth of data

I have a file of several scans per day for one year. I am using the OMINO2 product from the Aura platform. I am tasked with creating an automated process to: 1) Extract the sub-data set within the ...
2
votes
1answer
65 views

Defining projection using readOGR if the shapefile doesn't have it?

I think that by using readOGR to import a shapefile renders worthless to put proj4string to the script since if any coords are available in the shapefile, it will be transported through the readOGR. ...
0
votes
0answers
8 views

Lots of NaNs in reprojecting LSASAF to WGS84

I have a LSASAF file that has LOFF 1808 COFF 308 LFAC = 13642337 CFAC = 13642337 and the standard Euro dimensions NC = 1701 NL = 651 But when I try to translate the range col=1..1701, lin=1..651 ...
0
votes
0answers
59 views

How to set raster projection in R

I am new to R and grib files. library(raster) I have a "grd" file in and I am trying to set the coordinates to polar stereographic projection r <- raster("p190001.grd") # class : ...
0
votes
0answers
39 views

ogr2ogr re-projection produces empty shapefile

I use the following to re-project a shapefile to EPSG 4326 using ogr2ogr: ogr2ogr -s_srs "+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs" -t_srs "+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs" ...
1
vote
1answer
40 views

Is EPSG:3857 the correct projection for my PDF in Lambert Conformal Conic projection?

Given the following NEATLINE from the results of gdalinfo on my Geospatial PDF: NEATLINE=POLYGON ((-1340591.5297333347 -260482.28440259479,-1340591.0579001249 1878014.4171204455,3081498.0723039531 ...
2
votes
1answer
46 views

QGIS reprojecting .ecw file in EPSG:23032

I opened the .ecw file with qgis but I found that the ortophoto is 340 mt northern and 150 mt eastern the topographic map. How can I move the ecw?
2
votes
0answers
44 views

Reverse parameters of a projection map

I'm user of a soaring simulator named "Condor Soaring". This simulator is at the center of a community of enthusiastic people who build sceneries (landscapes) which represents quite accurately real ...
0
votes
1answer
140 views

How to convert latitude, longitude to EPSG 3857?

I'm looking to study the math involved to see how a given latitude and longitude in decimal degrees can be converted to epsg 3857. Can anybody point to a good reference or a possible python/c/c++/java ...
1
vote
1answer
64 views

How to use a different projection than EPSG:3857 with CartoDB or Leaflet?

I have data that is accurately positioned with the NAD 83 MTQ Lambert EPSG:3798 projection. If I reproject this data in EPSG:3857 (web mercator) the markers are no longer positioned accurately on the ...
1
vote
1answer
26 views

Change Projection

I am a little bit lost here. working in QGis 2.8, OS X 10.10. I have a polygon shp in the CRS EPSG: 21781, CH1903 / LV03 and a point file in EPSG: 4326, WGS84 How would I work with these ...
0
votes
0answers
28 views

Adding IF statement for Batch Projections

How do I add an "if" statement that will: 1) List all .tif files and their projections within the input directory 2) Copy all .tif and .shp files that are of the same projection from the input ...
1
vote
1answer
58 views

ArcGIS 10.2.1 projection Issue - Everything shifted west 50 m

I just completed hand-digitizing features on some NAIP (NAD83) imagery as a shapefile (NAD83...or that's what I thought I was doing). The coordinate system for the dataframe was NAD83, but now when I ...
3
votes
1answer
105 views

Obtaining length of non projected feature (gcs_wgs_84) in meters instead of decimal degrees?

I could not find a post which answered to my problem and I hope I didn't miss it, in case I did I apologize. I'm working with Arcgis 10 and I have a multiple lines feature with gcs_wgs_1984 ...
1
vote
0answers
39 views

ESRI/Mapinfo MGA56 prj vs QGIS MGA56 prj

I am trying to understand why the degree unit is different between ESRI/Mapinfo and QGIS: ESRI/Mapinfo ...
0
votes
0answers
81 views

Change SHP Projection to display on Google Map

I'm pretty new to GIS but not to programming, so sorry if this was already asked. I didn't find a solution not sure if I didn't quite understand everything about Projections and so on. I have a GIS ...
0
votes
0answers
25 views

How can I create a warp mesh to match two close but not identical datasets together?

I have two datasets for Mars. One of them is the Mars Viking color mosaic, the other the Mars Global Surveyor black and white imagery. When I overlay the two datasets, it becomes obvious that the ...
0
votes
0answers
18 views

Error in projection Qgis [duplicate]

qGIS- when I try to project using +proj=robin +lon_0=-150 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs In order to centre on the Pacific I get this: Any advice? Thank you!
0
votes
1answer
117 views

Displaying a map in EPSG:26915 projection in open layers 3

My GIS experience is limited to having worked on several Geospatial Humanities projects. That is to say that I still struggle significantly with the technology (and terminology) in getting to my goal. ...
3
votes
3answers
281 views

Which projection is best for mapping the contiguous United States?

If I wanted to project latitude & longitude data for the contiguous United States (the United States excluding Alaska and Hawaii), which projection would I use? I prefer more accurate distances ...
0
votes
2answers
128 views

How to change different projections of feature classes in geodatabase to one projection in new geodatabase?

I want to create a script that iterates through feature classes with different projections in a geodatabase and exports them into a new geodatabase, all with the same projections. What I want is to ...
0
votes
0answers
35 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
62 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
14 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 ...
2
votes
2answers
43 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 ...