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7

First install QGIS plugin "Affine Transformation" from Plugins > Manage and Install Plugins.. Then start editing and navigate to vector > Geoprocessing Tools > Affine Transformation. Add your latitude value in 'y+' as encircled in the screen shot.


1

Here is the answer I got back from NOAA. It's in the form of java code, and the order of parameters has to be inferred, but in case it proves useful to someone else here it is: public static final HTDP NAD83 = new HTDP(0.9910, -1.9072, -0.5129, 0, 0, 0, 1.25033e-7, 0.46785e-7, 0.56529e-7, 0.00258e-7, -0.03599e-7, -0.00153e-7, 0, 0, 1997); public static ...


2

There are no default transformations in the EPSG Geodetic Parameter Registry. Sometimes you can use the remarks and or the accuracy value to determine which is the currently accepted transformation as defined by the government or the most accurate transformation. For instance, in Belgium, there are two transformations between BD72 and ETRS89: 1652 and ...


2

The TIGER/Line data use Global Coordinate System North American Datum of 1983 (GCS NAD83). Based on About the 2015 TIGER/Line Shapefiles, each .prj file contains the following: GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137,298.257222101]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]] Which means ...


1

Its fairly easy with a bit of spherical geometry to work out the exact coordinates of a 50km circle centred at any lat-long coordinate. So you don't really need to use a buffer algorithm. On a sphere, every 50km circle is the same, just shifted to a new centre. So compute the coordinates for a 50km circle at the North pole (easy) and then apply a rotation ...


2

There's a lot of things to say here. First, there is no really one projected coordinate system which can cover the whole world without any distortion. Secondly, the units of WGS84 is degrees, so you won't be able to compute buffers in kilometers accurately. In my opinion, the best option is to use the geography type in PostGIS as explained here: What is ...


0

epsg.io allows you to search by country. Once you have a suitable EPSG code, you can extract using the links on the site. They also have an API, and the QGIS plugin called Search and Format EPSG code can use this to fetch the proj4 string (amongst many other formats), given the CRS. Or you can use a url like this for getting the proj4 string for ...


1

Boundless has an API for their projection to EPS that allows you to make calls using search strings.


1

SQL Server spatial functions implementation is in its current state not able to reproject or transform between different coordinate reference systems. The spatial data types are nothing more than a CLR (Coomon Language Runtime) data type implementation of the OGC Simple Feature Access specification plus some extended functions plus the spatial index. You can ...


2

You can calculate the UTM zone of each town center from the longitude, starting at zone 1 from -180°E to -174°E. zone=ROUND((183+longitude)/6;0) should calculate that in one step. The EPSG code is 32600+zone for positive latitudes and 32700+zone for negatives. Together in one formula: EPSG=32700-ROUND((45+latitude)/90;0)*100+ROUND((183+longitude)/6;0) ...


3

I would take a different approach and describe the spatial reference by directly calling the shapefile. For example: import arcpy arcpy.env.workspace = r'C:\your\workspace' shps = arcpy.ListFeatureClasses() for shp in shps: print arcpy.Describe(shp).spatialReference.name


1

About three months ago LAStools was updated to provide support for most EPSG codes to offer more ways to re-project with las2las. However, there are still two limitations: (1) the re-projection must use the same datum and (2) some of less common projections such as Hotine Oblique Mercator used by RSO Malaysia are not (yet) implemented. For those cases ...


1

afalciano has the right answer but wanted to include a variant usage of pyproj. It does require you know the proj4 string and is a tiny bit faster. import pyproj p = pyproj.Proj("+proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs") lon, lat = p(x, y, inverse=True) print lat, lon


1

From the Discus tab of the page: x y points are state plane coordinates Since Salt Lake City is in Utah, take all CRS that are valid for that state, and compare the location against an OpenStreetmap or other basemap. You will get lucky with EPSG:32043 NAD27 / Utah Central:


1

When you want to make a new layer from an attribute table, the coordinate system of the data should be mentioned in the meta data. And if it's not, you should find it through trial and error. For example here it is clear that the data has a projected coordinate system and it is belonged to Salt Lake city, so provide another layer of the city which has a ...


0

From what I see on the website (at least on a mobile device) this data cannot be downloaded in a native GIS format (like shapefile). If it could, such a format generally comes with various metadata, including projection info. Anyway, if you don't plan to combine it with data from other sources it doesn't matter what projection your GIS software thinks it ...


2

CSV files do not contain any CRS information, just coordinates. In QGIS, take a look at Settings -> Options -> CRS tab. Under CRS for new Layers you can choose Prompt for CRS. It might be set to a default CRS of WGS84 using degrees, and if the coordinates exceed +/-180/90, the CRS will be set to undefined. Apart from that, QGIS on MAC has some ...


2

The EPSG Geodetic Parameter Registry has two coordinate reference systems that match that well-known text. The first that I looked at was MGI 1901 / Balkans 7, EPSG:3909. The other one was Macedonia State Coordinate System Zone 7, EPSG:6316, which has the same definition. Using that information, I was able to find that the data is in Skopje, Macedonia. ...


2

Check ST_Transform from the very helpful PostGIS docs: SELECT ST_AsText(ST_Transform(ST_GeomFromText('POLYGON((-71.1776585052917 42.3902909739571,-71.1776820268866 42.3903701743239, -71.1776063012595 42.3903825660754,-71.1775826583081 42.3903033653531,-71.1776585052917 42.3902909739571))',4326),2249)) As wgs_geom;


0

Since you have the CRS parameters, you can assign that CRS to your data with gdal_translate: gdal_translate -a_srs "+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.999601272 +x_0=400000 +y_0=-100000 +ellps=airy +towgs84=446.448,-125.157,542.06,0.15,0.247,0.842,-20.489 +unity=m +no_defs" src_dataset temp.tif and then use gdalwarp to reproject the data to latlon ...


0

Lambert Conformal Conical has one or two standard parallels (latitudes), on which the scale is true. Mercator has one meridian (longitude) with true scale. So depending on the extent of your study area (more along the latitudes or longitudes) one of the two projections has less distortion. Once you have chosen a CRS, set the project CRS to it. For taking ...


3

Yes it will, I see nothing in this process that would result in a vertical datum change.


1

+no_defs - Don't use the defaults from the defaults file. +proj=longlat - This refers to a geodetic/geographic CRS. This means the longitude is the X axis and latitude is the Y axis.


0

If you're just using the smartphone GPS you probably do not need to worry about the conversion. The current difference between GDA94 and WGS84 is of the order of 1 metre, but you'd be unlikely to get a GPS location any more accurate than 4 metres in my experience. If differential GPS was being used however, it might matter. But if you are intent on ...


1

QGIS and ArcGIS will both convert directly between two projected coordinate systems. Internally, there may be some extra conversions to WGS84 or latitude/longitude on the input or output CRS but you don't need to handle it yourself. Please note that UTM is part of a projected coordinate system and a UTM zone can be based on many different geographic ...


1

You can go straight from NAD 1983 State Plane California -> UTM => export to .xyz. No need to go to WGS84. When you reproject to UTM, make sure you deal with the Datum correctly if it is NAD27.


0

It seems the projections are different. The first one in WGS84 and the second is in meter maybe in UTM Zone 36 since the landuse is located in Kenya. Try to project the first one to UTM projection. and see if they overlay each other. You may need to re-define the projection of the second one to UTM, if necessary.


0

You can do all of this with the "Project Raster" tool (in "Data Management Tools" > "Projections and Transformations" > "Raster"). There are a few things to consider here. If one of the rasters has a larger cell size, and it looks like one has a cell size of 98 (I'm not sure which one yet), you would do well to resample one of the rasters to the extent of ...


2

Have a look at the Define Projection tool and its code usage. As @dslamb points out, this method is used to assign a projection if one has not already been assigned, or if you wish to reassign a different projection. Once you have the desired SpatialReference object, you could do something like the following: arcpy.DefineProjection_management(projected, ...


4

QGIS relies upon the EPSG database, and since EPSG is a list of Earth-based CRSes, I don't think QGIS gives you a way to load your data in a "non-geographic" CRS. Since the data you are using is indoor location data, hopefully the coordinates are measured in something like meters or feet. If it is, you can choose any planar projection that uses the correct ...


-1

The data contains non-geographic x y coordinates If you can convert your data to a CSV or TXT file, you should give a try to Layer > Add Delimited Text Layer in QGIS. You can find an example here. When you will be asked to define the CRS, I suggest that you use WGS84 (QGIS use it by default).



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