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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.


4

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


3

Were the original pre-merge lines all pointing in a sea to source direction? If not then merging multiple lines flowing in opposite directions will cause the problem you are seeing. The solution is before you merge, you flip the lines that need flipping so they all flow from a source to sea direction.


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 ...


2

San Diego is in the State Plane California Zone VI (6) zone, and the coordinates are in US survey feet. The false easting and false northing values for that zone are 6561666.6667 and 1640416.6667. The false easting/northing values are often excellent indications of what coordinates should look like for that projected coordinate reference system (CRS). A ...


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;


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

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 – ...


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 ...


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 ...


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.


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 ...


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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