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1

You can do with arcgis project(Data Management) tool . It will convert from one coordinate system to any other. Go to arc tools and search for Project tool in Data management and give in put your vector file and give output coordinate system whatever you want based on your your requirements.


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Considering how the coordinates were originally arrived at confirms that what you are doing is correct. Look at point P1 in the figure. To determine where it is (without a GPS signal), the first step would be to identify where the up-down (vertical) direction is. Because gravity determines that, this direction must be normal to the geoid. Therefore P1 is ...


0

With the additional detail you gave in your other (meanwhile deleted) question it should be in Nigeria near Lagos. According to http://www.asprs.org/a/resources/grids/02-2009-nigeria.pdf, before switching to UTM, a CRS based at Minna named Modified Transverse Mercator was used in Nigeria. Available EPSG codes are: EPSG:26391 Minna West Belt EPSG:26392 ...


1

That diagram is greatly exaggerating the real but very small difference between two vertical directions: the normal to the ellipsoid, and the direction of gravity (normal to the geoid). The difference is called the deflection of the vertical. Unless you're doing very precise geodetic calculations, you can ignore it. In other words, it's safe to assume h = N ...


1

What I did to solve this problem was: I used the pyproj library to convert from WGS84 to Robinson as here: import pyproj crs_from = pyproj.Proj(init='EPSG:4326') crs_to = pyproj.Proj('+proj=robin +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs') x, y = pyproj.transform(crs_from, crs_to, LONGITUDE HERE, LATITUDE HERE) Then I realized ...


0

You can use QGIS for georeferencing (tutorial), then generate tiles with it (another tutorial). Finally, you should specify layer bounds in Leaflet tile layer with bounds option.


1

It is UTM co-ordinate system. It should be with proper zone number and north/South hemisphere. e.g See image:


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I'm not sure if Geotif format stores the EPSG code, or the whole projection definition in WKT or proj. If you compare the wo definitions: D:\Karten\gdal\gdal-1-11>gdalsrsinfo EPSG:32623 PROJ.4 : '+proj=utm +zone=23 +datum=WGS84 +units=m +no_defs ' OGC WKT : PROJCS["WGS 84 / UTM zone 23N", GEOGCS["WGS 84", DATUM["WGS_1984", ...


1

I would say that the ideal situation is to store everything in one table, with the same srid. However if that is not ideal in this case, I would consider creating a view that does an st_transform on the geometry to the srid you want and then use that to view in qgis.


1

if a feature class has a geographic coordinate system AND the buffer is performed with a linear unit (e.g arcpy.Buffer_analysis(input, output, "100 Feet"), ArcGIS will automatically use geodesic distance, which is great. Just make sure that you specify the unit


1

The feet and degree coordinates fit to each other if you use EPSG:2231 NAD83 / Colorado North (ftUS) with the following parameters: +proj=lcc +lat_1=40.78333333333333 +lat_2=39.71666666666667 +lat_0=39.33333333333334 +lon_0=-105.5 +x_0=914401.8288036576 +y_0=304800.6096012192 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=us-ft +no_defs Using QGIS ...


3

There is a similar formula described in this Esri forum post (for Washington State rather than Florida), so it is certainly a problem that's been addressed for a range of locations. The post refers to Map Projections, A Working Manual for the mathematical basics to modify the script for a different location. However, that would require some familiarity with ...


1

This answer is from an Esri help page, not QGIS, but the principle still holds true: A scale bar on a map that is set to a Geographic Coordinate System, using units of decimal degrees, only measures distances correctly at the Equator. To apply a scale bar that measures distances correctly over all areas of the earth's surface, the [map] must ...


4

You first need to decide what distortion properties would you like to control for. That is to say, are you interested in preserving area, distance or shape? There is a decision support tool for selecting projections that is quite user friendly and available for free from Oregon State University (Map Projection Selection Tool). Note that you can select the ...


1

You can use some projections that are provided by ESRI, depending on whether distance or area is important for you. They look very similar: ESRI:102032 South_America_Equidistant_Conic +proj=eqdc +lat_0=-32 +lon_0=-60 +lat_1=-5 +lat_2=-42 +x_0=0 +y_0=0 +ellps=aust_SA +units=m +no_defs ESRI:102033 South_America_Albers_Equal_Area_Conic +proj=aea ...


0

you should use labmbert or GCS WGS 1984 for entire Iran . These are the coordinate systems that use in Iran . NCC (www.ncc.org.ir) uses Lambert for Iran . If you work in a province then best option is UTM . If the province is located in two UTM Zone you should use GCS WGS 1984


5

On the page that you linked to, there is a note on the bottom: DATUM: SAD-69/original PROJEÇÃO CARTOGRÁFICA: UTM-22 (-51º) OBS.: Devido ao uso do DATUM SAD-69/original por Curitiba, para converter para SIRGAS-2000, devem-se utilizar os parâmetros locais de transformação de coordenadas descritos abaixo: SAD-69/original(Curitiba) -> ...


2

You might have used Set CRS for layer. This does not reproject any coordinates. Change it back to the original value, and use Save As ... using a different file name and EPSG:4326 as CRS.


1

Use crs function. If r is your raster: crs(r) <- "+proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0" Of course, you need to be sure it is the correct projection for your raster.


3

The map object will take on the projection of the first layer you add to it, in the case of your code, the streets basemap is 102100 (web mercator). You have two options to solve this: Use your own basemap service that is in your 102726 projection so that the points from the web service show up in the correct place. Stick with arcgis online basemaps, ...


3

These coordinates are expressed in Military Grid Reference System (MGRS). Thanks Andre for the hint!


2

Yes it is just the same. Web Mercator goes by 3 different srids (900913 and 3857 being two of them). I'm puzzled you don't have it. 3857 as I recall has been packaged with PostGIS for quite some time. Which PostGIS version are you running? SELECT postgis_full_version();


2

The problem is almost certainly with the "Sphere_Mercator" data. This projected coordinate reference system (CRS) is using a sphere-based geographic CRS. ArcGIS doesn't have any predefined geographic/datum transformations that convert to or from a sphere. The data may have been built on the sphere, or it might have been built on WGS 1984 and then projected ...


0

If you just want a reprojected dataset, the following libraries/Tools may help: proj4 (C++ library) provide transformation between different projections. GDAL/OGR (C++ library) provide transformation between different vector/raster format, support projection transformation if you specify compiling parameter forcing to compile with proj4 dependency. ogr2ogr ...


1

It's a two-stage solution: project geo-coords (lat, lon) to a Robinson map (N, E) transform the map (N, E) to a screen window (row, col) For stage 1, projection, you can use the ogr2ogr tool. Gothos explains how to use it for Robinson in particular transform-projections-with-gdal-ogr The EPSG library is extensive, but doesn’t contain everything, ...


1

The best tool for coordinate conversion is GDAL's cs2cs. The Lo 22/19 coordinate system is defined by EPSG code 29379, so the command line should be: cs2cs +init=epsg:29379 +to +init=epsg:4326 namibia_in.txt >>namibia_out.txt with this input file namibia_in.txt: 55435.89 -498157.28 Note that your coordinates are named Y;X but have to be ...


1

The Define Projection tool only changes the associated projection, it does not modify the geometry of the feature or shapefile. (Useful if you get data with no associated projection. Not useful if you're trying to transform to a different coordinate system.) Since you ran this before running Project (which mathematically transforms the data into a different ...


0

Quoted from About coordinate systems and map projections Other projections minimize overall distortion but don't preserve any of the four spatial properties of area, shape, distance, and direction. The Robinson projection, for example, is neither equal area nor conformal but is aesthetically pleasing and useful for general mapping. You may want ...


0

I posted an answer here which may help anyone who is having trouble importing/projecting CSV survey data: http://gis.stackexchange.com/a/109619/14731


0

Use XYZ coordinate system with origin at centre of the earth. Convert lat/long of the centre of the rectangle to XYZ. Then use 3D trigonometry to compute XYZ coordinates of the vertices. Finally, convert your XYZ coordinates back to lat/long. Procedure for doing the lat/long to XYZ conversion can be found here: www.ngs.noaa.gov/TOOLS/XYZ/xyz.shtml


0

You don't have to set the coordinate system if you have the "on the fly" option enabled. If you set the EPSG manually qgis thinks that the coord are in "GDA94/MGA Zone 50" and use the layer without transformation. Always remember that projecting "on the fly" could be a bad thing.


3

Yes, you are right. Finnish nautical maps printed 2002 or before are all based on KKJ coordinated system. KKJ coordinates may differ from GPS-coordinates (WGS84) as much as 200 meters. Starting from 2003 have all new nautical charts been published in EUREF-FIN (appr. WGS 84). These new nautical charts apply international INT chart symbols. Because shallow ...



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