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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.


0

If the county map is in EPSG:2237, better leave it that way. DO NOT use Set Layer CRS to change it, that will corrupt your data. If you did, change it back. Better use Save As ... for vector data and Raster -> Projections -> Warp for rasters. Both need another filename and a different target CRS. If you are unsure, set the PROJECT CRS to EPSG:3857, ...


4

If you want to transform coordinates to another SRID, you will use ST_Transform: SELECT ST_AsText( ST_Transform('010600002031BF0D0001000000010300000001000000050000008FEF9C07089AFEC0B90A9856E87251410F355DB1B395FEC0DCCEADDCED72514194BE3130A693FEC0DFD23127D072514114797186FA97FEC094E0C313CB7251418FEF9C07089AFEC0B90A9856E8725141' ...


1

You can use the ST_AsText function to get the WKT representation of your geometry, this will return the coordinates in whatever projection you have. (You will only get the latitude and longitude if your data is stored in a Geographic Coordinate system, SRID 4326 works for most cases) You can use this query to change SRID ALTER TABLE table     ALTER COLUMN ...


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I think this is done using the WikiProject Geographical coordinates: WikiProject Geographical coordinates aims to better organize location information in articles containing a set of numbers that identifies location on and relative to the Earth.


1

Yes, they will be square in both projections! Breaking it down: UTM stands for Universal Transverse Mercator. From the Wikipedia article: The Universal Transverse Mercator (UTM) conformal projection ... i.e. UTM is "conformal." As for what "conformal" means, again from Wikipedia: Conformal, or orthomorphic, map projections preserve angles ...


1

There's a reason UTM projections don't extend to infinitive and engulf the whole globe. As you move further away from the UTM's central meridian the distortion becomes more and more apparent. In the case of a transverse Mercator projection the distortion, as its a conformal projection, is applied equally both in the X and Y axis, therefore your angles ...


2

The transverse Mercator Projection is conformal and preserves angles. So the square should still be a square. Area will change though.


2

From the precisions you provided in the comments, I understand that what you want is actually a polygon merging followed by some kind of vertices coordinates export. This is actually quite simple: Merging: Select your layer then click on the pen icon to toggle edition mode. Select your two polygons, then go to Edit > Merge Selected Features. This will ...


1

Do you mean you want a boundingbox? Then read the record, draw the first point with the VertexCreator, add the second point with another VertexCreator and replace the geometry with the BoundingBoxReplacer.


2

I did port the Python code to php: <?php function parseFloat($ptString) { if (strlen($ptString) == 0) { return false; } $pString = str_replace(" ", "", $ptString); if (substr_count($pString, ",") > 1) $pString = str_replace(",", "", $pString); if ...


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 ...


1

You'll want to do a Spatial Join from the Overlay toolbox in the Analysis Tools toolbox in ArcToolbox. For the match option select CLOSEST —The feature in the join features that is closest to a target feature is matched. This assumes your landuse layer with points of interest is a feature layer, not a raster layer.


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This is possible with QGIS without extra plugins using the Advanced Digitizing panel. This tool allows entering exact coordinate values as well as constructing points at given distance and angle from other points. Pictures taken from this excellent answer which gives a walkthrough.


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Another option is to use QGIS's virtual layer functionality. Just click the 'Add Virtual Layer' icon near the bottom of the left hand tool bar and enter the following into the query window (subbing your values for the parameters in the MakePoint function): SELECT 1 as id, MakePoint(x, y, srid) as geom If you want to create multiple points this syntax ...


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;


1

I too went through a lot of frustration getting the QGIS clipping polygon process working. Most of the problem was CRS related I'm sure. For what it is worth, the following well-tested detailed steps might help a novice like myself, even if overkill to the more advanced QGISers. I'm using QGIS 2.14 Essen. Run QGIS and load the layer to be clipped – ...



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