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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1k views

Finding projection of point to line?

I have a segment defined by 2 LatLon points(A and B) and a third LatLon point (C). I need an alghorithm, formulae, or some code to find the projection point of C on the segment AB (call this point D) ...
2
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0answers
25 views

ArcGIS project raster mosaic bends the raster but not the footprint when projecting

I have mosaic whose rasters are using a custom coordinate system: US_IFR Authority: Custom Projection: Lambert_Conformal_Conic false_easting: 0.0 false_northing: 0.0 central_meridian: -95.0 ...
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0answers
21 views

Reprojecting and Aggregating a 30m resolution raster to a 3 arcsec raster

I am a using a 30m x 30m resolution land use raster that is projected in NAD83 Québec Lambert but would like to convert it to make it compatible with a 3 arcsecond flow accumulation raster that is ...
2
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0answers
57 views

Getting Error 000151 from ArcGIS Projection? [closed]

I'm having big problems with arctoolbox of ArcMap 10.3.1 to project almost all my layers from TM65 - Irish Grid to IRENET95 - Irish Tranverse Mercator.I always get the error 000151 and the Help is ...
2
votes
1answer
38 views

Area calculations using a layer in a projected data frame versus a projected feature class in ArcGIS

So I've been tasked with automating a formerly manual process in model builder in which I'm trying to calculate land area. In the former manual process the feature class was brought into ArcMap and ...
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0answers
46 views

Gdalwarp UTM reprojection causes image distortions

I'm trying to re-project Sentinel-2 images to a common UTM zone in order to create a mosaic. For this I'm using gdalwarp with the following syntax: C:/OSGeo4W64/OSGeo4W.bat; gdalwarp -t_srs \"+proj=...
2
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1answer
51 views

Produce Oblique Mercator Map

To avoid the possibility of opinions, let me rephrase the question. Which software packages are able to produce an Oblique Mercator map between any two arbitrary points, similar to what is offered in ...
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2answers
144 views

Reproject raster without projection info

I'm pretty new to gdal and got a presumably easy question for experienced gdal users. My problem: I have a raster ascii file of which I don't know the projection or epsg code. However, I want this ...
2
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1answer
34 views

Web Mercator to 3d globe projection problems

I've been trying to use map tile images from services like OpenStreetMap to create a globe, and I've mostly succeeded. The problem is that when I compare my globe to one using the same image source ...
2
votes
1answer
55 views

Problems with matching vector data with raster data

I’m new in Arcgis, and I have some trouble in this task: I downloaded from ICC (www.icc.cat) a raster data map that is a in a specific coordinate system, if I right click to view its properties, it ...
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2answers
232 views

Defining coordinate reference system with rotation in GeoServer?

I am using GeoServer and have a layer in EPSG:900913 ("Google Mercator"). I need to "rotate" the map around certain point (say, 1500000, 7000000) by certain degree (say, 30 degrees clockwise). How ...
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2answers
60 views

D3 can't render GeoJson file (Simple structure in Montreal, Canada) created in QGIS

I am attempting to render SVG and attach it to a div with id="map". I can do this successfully with GeoJson which I acquired from this tutorial: http://maptimeboston.github.io/d3-maptime/#/1 Excerpt: ...
3
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2answers
83 views

What kind of projection is this?

Can someone tell me what the projection is in this zone map from NOAA? I am trying to replicate it (or get close) in QGIS.
1
vote
1answer
22 views

Discrepancy between shape area and data from municipality [closed]

I am attempting to map several parcels just to show very basic dimensions (frontage, etc.) and parcel area. I have the parcel area from the municipal assessor's office in acres. And I have a parcel ...
0
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1answer
47 views

Can gdalwarp reproject from ESPG:4326 (WGS84) to UTM?

I've a GeoTIFF image in ESPG:4326 (WGS84) and when I try with gdalwarp to reproject to UTM, it has problem gdalwarp -s_srs "EPSG:4326" -t_srs '+proj=utm +zone=33 +datum=WGS84 +units=m +no_defs' -of ...
2
votes
2answers
84 views

OpenLayers 3 / Cesium polygon projection issue

I am using OpenLayers 3 and Cesium (via ol3-cesium). I have created a few rectangles (using a MultiPolygon) stacked on top of each other. Whereas in OpenLayers the rendering (left) is as expected, ...
2
votes
2answers
101 views

Is it possible to restore lost PRJ-Files?

Currently I am working on a project with QGIS (2.14.1). Therefore I need to add old (but important) shapes that were drawn by a colleague. Somehow most of the .prj-files are missing - I don't know ...
4
votes
2answers
119 views

Openlayers 3 connecting to a wms feed with a different projection

I am trying to incorporate a wms feed in the British national grid projection (EPSG:27700) into a openlayers 3 project. I initially had used this wms layer in an openlayers 2 application using the ...
2
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0answers
60 views

Creating Proj4 string for local coordinates

I am fairly new to coordinate system conversion, so am rather lost on the following problem. We have been using Proj4 to convert between various coordinate systems which is fine for known coordinate ...
0
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1answer
191 views

Check if point is within radius of another point with Shapely

I've successfully used Shapely with python to check if a point is within one of a set of polygons in a .shp file but now would like to check if a point is within a circle of radius x miles from ...
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vote
1answer
35 views

R: Krovak projection in R - identical in ArcGIS, different in R?

I have two files: shapefile and raster, both in the same coordinate system in ArcGIS: EPSG 5514. Check information on projection in ArcGIS for raster: S-JTSK_Krovak_East_North WKID: 5514 Authority: ...
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2answers
296 views

Mapping Russia - Int'l dateline splitting polygon

I am having the issue where the International Dateline is splitting a polygon I am working with. I have a layer of the "Federal Districts" of Russia, and the eastern most federal district is being "...
4
votes
2answers
601 views

Project twitter geo data into WGS84 map

I'm currently working on displaying twitter geo data (currently just long/lat -> cartesian without any analysis). This is the world map (source: naturalearthdata): http://dl.dropbox.com/u/14747311/...
5
votes
1answer
2k views

Projected maps should but do not overlap in ArcMap? [duplicate]

I am very new to ArcGIS and trying to build a series of layers of data in ArcGIS 9.3.1 for a river catchment in Leicestershire, using data from several sources. All data covers at least the area of ...
9
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3answers
5k views

Shapefiles and OpenStreetMap data do not overlap in QGIS?

So I'm pretty new to GIS, and I'm working on a mapping project using data for Vancouver, Canada. I want to combine OpenStreetMap data along with data provided by the City of Vancouver. But the City ...
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0answers
6 views

How do I display NAD 1927 Albers with other data?

I have some raster datasets which are in NAD 1927 Albers projection. I cannot seem to display any other type of data with this projection. I get the pop-up projection warning when trying to add a ...
3
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0answers
26 views

How to do a custom, ad hoc, affine transformation?

I have a data set of unknown origin (probably CAD) and I have determined that the correct transformation for this data into the projection that I want is as follows: (4x + 2205432), (30y + 1254781) ...
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26 views

RD new to WGS 84 conversion

i want to display 2d building shapes and 3d buildings as presentation purpose.i m using Arcglobe for it.i have shape files with projection EPSG:28992.i have converted it into WGS 84 but my shapes does ...
2
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0answers
42 views

Re-projecting shapefile from an unknown projection [duplicate]

I have been given a shapefile which is supposedly in a NAD1927_Zone16 projection. I need to align it with a raster image in a Lambert Conformal Conic (NAD 1927) projection. I've tried to use the ...
2
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0answers
38 views

Calculate Geometry function returns underestimated distances

I'm making a map of the Colorado Trail and obtained a set of waypoints taken down the entire trail. I projected the set of waypoints from WGS84 (unprojected) to NAD 83 UTM13N after adding to the data ...
3
votes
1answer
88 views

Coordinate points not lining up with a preexisting map on QGIS

I asked this question once before, but I did not receive any feedback on solving on the issue and I am still confused as to what I am doing wrong. I found a public domain map of Florida counties on ...
5
votes
1answer
736 views

Is there any Google Maps-like zoomable world map, but with an equal-area projection?

Whenever I look at Google Maps at a global or polar area, the projection hurts. Is there any web service with a zoomable world map, that uses an equal-area projection — preferably pseudorectangular ...
3
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0answers
38 views

Rectangle shapefiles with the same extents does not align perfectly after projection

I have a rectangle shapefile built with UTM19 coordinates using a python script, and then projected to NAD83_CSRS (EPSG:4617). I have a second rectangle shapefile built with the same method (python ...
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0answers
15 views

Openlayers Reprojection from 4326 to 3395 is wrong?

I'm using proj4js definitions downloaded directly from epsg.io webpage. When trying to reproject a small extent I get this result: ol.proj.transformExtent([-180, -90, -179, -89], 'EPSG:4326', 'EPSG:...
3
votes
1answer
110 views

Change the actual coordinates in a shapefile (QGIS)

I'm trying to map data for a county in Texas. The data were provided to me in a shapefile, and I've been working with it in QGIS 2.14. My problem is this: The coordinates in the shapefile I was given ...
0
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0answers
27 views

Problems to export raster files in R software

I'm working with R software with raster and netcdf4 packages adn netcdf files to get information from SST. I got the information and now I'd like to convert in ascii or geotiff files to work in ArcMap ...
0
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1answer
30 views

Background color changes when projecting a raster with ArcGIS 10.4

I'm using the Project Raster tool via arcpy: arcpy.ProjectRaster_management( in_raster = clipped_raster, out_raster = projected_clipped_raster, out_coor_system = ...
0
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1answer
27 views

How can i project a coordinate system for many rasters all at once? [duplicate]

help many rasters i have and should be projected in UTM coordinate system. what should i do?
4
votes
1answer
258 views

Choosing Projection for Gulf coast region of USA?

What are the most appropriate datum and projection I could use for the Gulf coast region - spanning Louisiana, Mississippi, Alabama, and Florida? I have to analyze block group data along the coast.
5
votes
3answers
117 views

Are perpendicular lines still perpendicular after converting from UTM zone 15 to 16 (or between two neighboring zones)?

I want to convert a square polygon that is close to the edge of UTM zones 15N and 16N. The polygon's coordinates are in UTM 16N, but it is spatially positioned in the UTM15 area. My question is that ...
3
votes
1answer
22 views

Strange Custom Projection can't be transformed

I've got a a database of feature classes that were somehow transformed into a custom projection that I don't understand, and there does not seem to be a way to get back out of. The projection data ...
0
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0answers
25 views

GCS_Clarke_1880 transformation to GCS_WGS_1984 in ArcGIS 10.3.1

ArcGIS 10.3.1 has no transformation for GCS_Clarke_1880 to GCS_WGS_1984. Why is this the case, what have I missed? Do we have to write a custom transformation? There are a heap of Clarke ...
2
votes
0answers
49 views

Converting from unknown coordinate system into common one using fiducial points?

I have a thousand of points that I want to project in a different coordinate system. These points were generated using an old and odd coordinate system (let's call it CS) so it's not possible to use ...
0
votes
2answers
77 views

How to check my EPSG and units in R when it is not defined in proj4string?

After reading my .shp in R using readOGR(), I tried to figure out what is my EPSG and what are my units in my projections? when I tape my.shp = readOGR(dsn=setwd(dsn = dsn, my....
3
votes
2answers
672 views

Displaying map tiles from GeoPackage

Is it possible to translate tile requests from a mapping engine wanting Google Map style tiles into tile requests from a geopackage file? If not, where can I find information about how to create a ...
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0answers
51 views

PostGIS Svg Projection on Google Map

Context I have a database with spatial data such as areas and points. Some of the areas in my db are coming from OpenStreetMaps, representing some regions. (Which are kinda small at earth's scale, ...
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vote
1answer
29 views

Why is my imported map showing up so small in ArcMap 10.2?

I have .asc files that contains a map of a predicted species distribution I got from using MaxEnt. When I import the file with the data frame properties set to North American Albers Equal Area the ...
3
votes
2answers
723 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 ...
3
votes
1answer
147 views

Tilted projection in QGIS

I'm trying to add tpers projection as a custom projection in QGIS 2.10.1 In the Custom crs dialog I'm adding the proj.4 text: +proj=tpers +h=500000000 +lat_0=19 +lon_0=99 +x_0=0 +y_0=0 +a=6371000 +b=...
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0answers
24 views

C# selecting map tiles from user defined rectangle points?

I have a WPF user control with which the user can draw a rectangle on the map canvas to define an area for downloading background imagery tiles from a web service. The tiles are in Lat long 1x1 degree....