Questions tagged [values]
The values tag has no usage guidance.
66
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Select points with maximum value in each polygon
I have Census areas as polygons and Census population counts as points at a lower geographic level (i.e., there are many points within each polygon). I need to select 1 point from within each polygon ...
1
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1
answer
37
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I can't update any attribute values in PyQGIS
I've been using PyQGIS for a few of weeks. I'd write a script which shows all earthshakes responding to given parameters, so I wrote this code:
from PyQt5.QtGui import *
from PyQt5.QtCore import ...
- 11
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20
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Reclassify by table
I'm using IFSAR 5x5 DEM Raster and run a Reclassify by Table with only 5 values 1, 2, 3, 4 and 5. Then I converted the reclassified raster into Polygon. When I checked the attribute table the values ...
2
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2
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91
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QGIS Value Relation Widget saves not the KEY COLUMN values but the VALUE COLUMN values in the attribute table
As far as I know, the "Value Relation Widget" is supposed to store the records from the field designated as KEY COLUMN in the attribute table, while the records from the field designated as ...
3
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239
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Importing CSV results in NULL values for decimal column in QGIS
I am importing a .csv file and one of the "integer" columns ("ZVH Density") is all NULL values when imported as a Delimited Text file. Whole numbers import (known through trial and ...
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I am trying to produce a LULC using supervised classification , but I got an out-put in gray color
I am trying to produce a LULC using supervised classification , however, I am getting an output in gray color. Anyone knows what is the issue?
// Supervised Image Classification with Landsat 8 ...
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22
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Generating new polygons based on sum of values
I am working with QGIS, and I have created the styled density map with the hexagons to calculate pop figures within these. The pop field is displayed inside each polygon.
I now want to create new ...
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193
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Connecting points to the two closest highest values grouped by category
In a points layer with the fields "POP" (corresponding to the population value) and "CATEG" (corresponding to municipality id), my goal is to connect the points of each ...
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94
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QGIS attibute form with value relation avoiding table
Is it possible to use some expression or text containing a values list for the dropdown control to display them?
The goal is to use a short list of values and not have to create a related table for ...
- 2,419
3
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242
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How to recover parent value while creating parent and child layers in a embedded forms setup?
I read the documentation, examples and made many attempts, but I still can't make this work.
What I want is to get a value from a parent layer while editing a child layer, when both features are being ...
- 567
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86
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QGIS 3.22.16 Bialowieza. Selecting matching value in 2 fields
I am using QGIS 3.22.16, I try to select similar 'null' value in 2 different field. I tried the solutions suggested from one this exchange.
Selecting features with equal values in different fields in ...
- 321
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Autofilling based of value map in QField
Is it possible to prepare a Value Map with autofilling? I have a list of almost 500 plant names and it is difficult to find correct name on my device (phone with Qfield) while scrolling. Is it ...
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375
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QGIS 3.22: problems with dropdownlists (attribute forms)
I discovered the nice possibility in QGIS to create dropdown lists in a field, with which I (should) choose in a simple way one of several species (in my case) - while entering new features. I tried ...
- 483
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522
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Display expression of layer if geometries intersect in QGIS [closed]
I'd like to display the value of a layer (polygon with parcels) only in case a line (f.e. a river) intersects, crosses or touches the polygon of the parcel by using the expression dialog... but I ...
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334
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Extracting minimum pixel value from multiple rasters
I am trying to extract minimum values from about 300 raster files (GeoTIFF) - for example an output table containing raster names against their minimum values. I would like to automate the process. I ...
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