9
votes
Accepted
Accessing layer properties for expression syntax in QGIS Modeler
You can use Raster layer properties:
@Raster_layer_properties_PIXEL_HEIGHT > 15
The conditions are used as dependencies to the following tools:
If the input raster has a pixel size above 15: ...
- 76.2k
8
votes
Adjusting coordinates from whole vector layer in QGIS
Solution
You are using the Swiss national grid which exists in two versions:
The coordinates in your layer are in the "old" style: CH1903 / LV03, corresponding to EPSG:21781 ( fundamental ...
- 73.8k
8
votes
Accepted
SRID in PostGIS -> ST_SRID !== Find_SRID
Excursion:
PostGIS (custom) data types utilize the PostgreSQL type mod[ification] system that allows for flexible, system-accessible meta data storage alongside the actual values; for both data types ...
- 30.6k
7
votes
Accepted
How to define (not reproject) a CRS of a shapefile in QGIS?
There is two tool for that (the first one create a copy of your layer, the second one create (or overwrite an already existing) projection):
Assign projection
This algorithm assigns a new projection ...
- 16.8k
7
votes
How to define (not reproject) a CRS of a shapefile in QGIS?
Simply right-click the layer in the Layers panel > Layer CRS > Set Layer CRS... - no new layer will be created, simply a new CRS definition is assigned to the layer in QGIS (the data itself ...
- 73.8k
7
votes
Accepted
ST_Within fails with local CRS but works in WGS84?
This is a common issue when re-projecting huge polygons between geographic and projected coordinate systems when the geometries have only few vertices. The projection algorithms re-project just the ...
- 68k
6
votes
Accepted
TAB file can't be saved in EPSG:3414 using QGIS
QGIS is using GDAL for dealing with the MapInfo data. MapInfo has a little special way for handling the coordinate systems. GDAL maps the CRS definitions into native MapInfo syntax as well as it can. ...
- 68k
6
votes
Orientation differs between projections. What is the "Real" North?
As others have pointed out, orientations measured in GIS will always be relative to "grid north" for a particular projection. The relationship between grid north and true north varies ...
- 3,077
6
votes
Adjusting coordinates from whole vector layer in QGIS
If you are sure there is nothing wrong with your CRS you can use "Translate" from the Processing Toolbox (Ctrl+Alt+T). Simply set your X and Y values and run it:
e.g result (brown original ...
- 35.2k
6
votes
Selecting metres when using QGIS Points Along Geometry
GPX file coordinate are by definition expressed as decimal degree using the WGS84 datum. You can't save a GPX file in a CRS with meter as unit. (and yes the QGIS "Save Features as" window is ...
- 16.8k
6
votes
"Could not load source layer for INPUT" error when reprojecting flt-file with PyQGIS
I would agree with @BenW's comment, that your binary floating-point files can not be found under this path inputfolderpath + '/' + fltfile_name. However, I could also say, that your input does not ...
- 33.7k
6
votes
Accepted
Is this KML file measured in degrees?
KML is an OGC standard where longitude/latitude are in decimal degrees (based on WGS84 ellipsoid) (Altitude is measured in meters from the WGS84 EGM96 Geoid vertical datum, but you don't seem to have ...
- 16.8k
5
votes
Accepted
Setting decimal places in coordinate-grid in QGIS Print Layout
You can set the precision: "Map Grid Properties" in the "Draw Coordinates" section at the bottom.
- 11.7k
5
votes
Accepted
Projecting an old Ordnance Survey map in Cassini-Soldner Grid
The NLS web site tells us that the maps are constructed on Cassini's projection with a point of origin at Delamere Forest:
https://maps.nls.uk/os/quarter-inch-third/
Which Wikipedia sites at: 53.2291, ...
- 65.6k
5
votes
Accepted
Leaflet offset of tiled layer WMTS layer
The main problem is in the tile grid. WMTS layer from https://wmts.asit-asso.ch/ has the same projection, but different tile grid. There are some maps available from asit-asso.ch on https://asit-asso....
- 26.5k
5
votes
Calculating azimuth between two points using their projected coordinates with Python
Since your coordinates are on a Cartesian plane you can use the trigonometry that you learned in high school. Your coordinates are a right angled triangle with sides of dx=Math.abs(x1-x2) and dy=Math....
- 82.6k
4
votes
Compute the area of differents buildings for differents regions in GeoPandas
You can use groupby each row, reproject it using .estimate_utm_crs, and measure the area:
import geopandas as gpd
file = r"/home/bera/Desktop/GIStest/worldwide_squares.gpkg"
df = gpd....
- 76.2k
4
votes
Accepted
Trying to determine which CRS this GML uses
Use projfinder.com. Stick your coordinates in the box, zoom the map to where you think the point should roughly be, click "Find My Projection" and it scans thousands of projections and sees ...
- 65.6k
4
votes
Identify feature issue
In QGIS, one of the layers is always the active layer even if you do not select it and the selection is performed in the active layer. When you select any layer, you make it the active layer.
I used ...
- 77.8k
4
votes
Orientation differs between projections. What is the "Real" North?
The North of a projection refers to the projection's own definition.
Projections can be rotated or otherwise distorted in relation to the geometric body they project to a plane.
If you need ...
- 11.2k
4
votes
Accepted
Is there a comprehensive list of mapnprojections implemented in R?
The projections and projection operations are not implemented in R directly - but in PROJ, which is a standalone library at system level. This library is integrated with R somewhat loosely - you can ...
- 1,145
4
votes
Accepted
Incompatible numeric format between points and polygons geometry in GeoPandas
Reproject so the dataframes are in the same crs:
Transform all geometries in an active geometry column to a different
coordinate reference system
I want both in EPSG:4326:
print(poly.head(2))
# 0 ...
- 76.2k
4
votes
Accepted
Wrong parameters when georeferencing single drone images
My experience is with a Mavic Mini, which does not have published lens distortion specs and has only consumer-grade GPS, not RTK correction. With that caveat in mind, I've found you just need to ...
- 8,316
4
votes
How to make an infinite repeating projection in QGIS
See https://github.com/qgis/QGIS/issues/30902. Not possible at the moment, otherwise, QGIS issue would be closed whereas it remains opened.
There is also a similar question where there was never an ...
- 31.1k
4
votes
Accepted
How to make annotations follow the latitude lines in QGIS?
Follow the instruction in this solution.
To rotate the labels in the upper part to be upside down, in the label settings got to the tab Rendering -> Show upside-down labels and check the box ...
- 73.8k
4
votes
QGIS custom CRS definition error
Coordinate frame method and its parameters are in XYZ, 3D geocentric space, while your parameters are part of a 2D conformal, or similarity, transformation--they're applied to the easting, northing ...
- 19.1k
3
votes
Problems importing DJI Phantom images into QGIS
"Coast of Africa" sounds like Null Island. This is very likely a CRS-Issue.
However, your point's are at the right location so probably it worked just right. And the import-photo tool ...
- 1,412
3
votes
Transcribing subdivision coordniate geometry in QGIS
This is really a comment but it is too long for that box. Many if not most of the old survey/plan maps I had to deal with were created without any reference to a coordinate system. Your snippet looks ...
- 1,809
3
votes
Finding all layers not using the project CRS in QGIS
You can use QGIS expressions with the following expression to get a list of all layernames that are in another CRS than the project CRS. You can apply the expression wherever you can use expressions: ...
- 73.8k
3
votes
Which projection is best for mapping the contiguous United States?
Snyder's GS48
PROJ has a Modified Stereographic of 48 U.S. (+proj=gs48) projection:
It is based on a modified-stereographic conformal projection detailed by Snyder (1987) (p.203–212). Here is the ...
- 42.2k
Only top scored, non community-wiki answers of a minimum length are eligible