Questions tagged [layers]
A layer is a collection of information. It contains specific elements of a gis in a specific presentation method (e.g raster or vector layer). Layers can be edited separately in order to create individual topics for a map.
2,298
questions
22
votes
2
answers
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Adding shapefile or feature class as layer in ArcMap using ArcPy
I am trying to automate various tasks in ArcGIS Desktop (using ArcMap generally) with Python, and I keep needing a way to add a shapefile to the current map. (And then do stuff to it, but that's ...
- 429
22
votes
5
answers
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Using layer loadstart & loadend events in OpenLayers 3?
OpenLayers 2 has these layer events "loadstart & loadend."
What is equivalent to them in OpenLayers 3?
While a vector layer loads and is rendered, I need to show a loading icon.
- 603
21
votes
7
answers
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How to improve rendering performance of a very large shapefile?
I have a polygon shapefile that has a 100MB .dbf, and 500MB .shp file component. The reason it is so large, is that it is classified as a landbase for a whole district.
Everytime I view the file in ...
- 574
20
votes
3
answers
11k
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Getting layer extent using PyQGIS
I'm trying to write a processing script using grass r.neighbors algorithm for rasters. When you use the GUI for this algorithm, you can leave the GRASS layer extent field blanc to use the minimal ...
- 765
19
votes
3
answers
8k
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Duplicating layer in memory using PyQGIS
I have a layer in QGIS, and I want to duplicate it through a plugin so I can use the copy of it as I want, without modifying the original.
Of course layer2 = layer1 will not work, because everything ...
- 375
19
votes
3
answers
29k
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How to perform a true GIS clip of polygons layer using a polygon layer in R?
I would like to do a true GIS Clip in R of soils polygons using a series of single boundary polygons, but I cannot find an R function to properly do it. It should work just like the clip function in ...
- 191
18
votes
2
answers
791
views
Showing the number of currently selected layers in QGIS
Although this should seem to be very straightforward, I cannot find out how to see the number of layers I have currently selected in QGIS. For example, in the example below I want to see somewhere in ...
- 771
17
votes
3
answers
8k
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Using ArcPy to get layer symbology?
Since ArcGIS 10 comes with the ArcPy package, I'm wondering it is possible to use ArcPy functions to get Symbology (i.e color, width...) of a layer?
- 1,470
17
votes
1
answer
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Making layer or group private/hidden/invisible in Layers Panel of QGIS
I have a number of layers in the Layers Panel inside a group but I don't want them shown (there's quite a lot so it looks untidy). These layers are also joined to several others.
Is it possible to ...
- 76k
16
votes
2
answers
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Getting list of layer names using PyQGIS [duplicate]
I need a list containing the names of all the layers in a QGIS session. I did the task as
layersNames = []
for i in self.iface.mapCanvas().layers():
layersNames.append(str(i.name()))
but this has ...
- 749
16
votes
3
answers
8k
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Getting field names of layer using PyQGIS
How does one get a list of attributes/field names of a layer by means of PyQGIS 3?
If my layer has field names seen in the attribute table or properties. How can I use PyQGIS to give me a string list ...
- 1,063
16
votes
7
answers
35k
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Getting extent of layer in QGIS
Is there a way to get the extent (bbox) of a vector layer in QGIS?
I see that I can update the extent, but I am looking for the actual coordinates of the extent.
- 8,024
16
votes
4
answers
10k
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Adding layer to GeoPackage using PyQGIS
How to add layers (vector or raster to an existing GeoPackage)?
While loading an existing layer of a GeoPackage is quite trivial:
from qgis.utils import iface
path = '/home/matteo/geopackage.gpkg|...
- 3,304
16
votes
4
answers
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Compare similar lines and update layers
Here there are two layers with the representation of the streets and the idea is: We want to update the most recent layer (with the red line) with some of the data storaged in the other one (the light ...
15
votes
5
answers
27k
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Removing feature layer using ArcPy script
I have an ArcPy based script where I'm trying to intersect two layers where one layer must have its centroid in the other layer.
Since I need to know that one layer (feature_layer below) includes the ...
- 1,716