Questions tagged [values]
The values tag has no usage guidance.
62
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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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16
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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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5
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1
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162
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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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3
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45
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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 ...
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3
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121
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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 ...
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1
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78
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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 ...
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65
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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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3
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181
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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 ...
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324
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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 ...
- 509
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26
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Use displayed values instead of raw data in joined tables
(I believe my question is directly linked to this one, but the answer is incomplete)
I have a large QGIS project with multiple forms using hundreds of "value relations" to create dropdown ...
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-2
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2
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268
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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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85
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How to highlight by gradient specific range of values from the same field in QGIS?
There is a field about alcohol consumption by country with 10 max. and 10 min. values (picture 1).
Need to choose only 10 max. values and create a gradient map. Seems its needs to be some expression, ...
- 327
2
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414
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Setting default value in QGIS field using QgsEditorWidgetSetup in PyQGIS
There are many questions like this but either they propose to implement a new method to update values or describe how to set default values for fields in GUI.
I'm writing a QgsProcessingAlgorithm and ...
- 167
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17
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Alternate view to normal view in attribute table [closed]
I have somehow accidentally changed how my attribute table looks and I dont know how to get it to go back to the original state has anyone any idea how to change?
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270
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Invert raster's min with max values (as well as the in between values) and vice versa using R
I have a raster with pixel values, 1 to 255 (no decimals). I want to invert their values in a way that pixels with value 1 will get value of 255, pixel with value 2 will get 254, pixel with value 3 ...
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105
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LANDSAT-7 strange strip on SWIR bands (B5 and B7)
I was exploring Landsat 7 data on SentinelHub and came across with this strange strip in the SWIR band B7 (also B5):
By placing a pin in this strip and exploring the stats, I found that there is no ...
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3k
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How to get the number of pixel with a given value from a RasterLayer in R?
I'm working with Corine Land cover data. I want to assess the number of pixels with any forest value (311, 312, 313, 321, 322, 323, 324) of two reference years. That's wat I did:
clc00 <- raster(&...
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35
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Nested for: I execute changeAttributeValue in the outer loop, print it and is still NULL... but inner loop works kind of fine?
A bit hard to explain, untill now my script is:
I have a for, where:
if an "Analized" attribute is NULL, I will change it to "Parent",store a "Join Value" attribute in a ...
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100
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Extracting average value at point using ArcGIS Pro
I have a dataset of over 500 points that represent the location of a number of site boundaries and a Tif file displaying the wind speed data over the study area.
Is it possible using ArcGIS Pro to ...
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92
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pH = 0 in pH layer
I have downloaded the pH layer from ISRIC database. However, when I added it to QGIS, I found it contained lots of points with the values = 0 (red points in picture).
Can I treat those 0 values as NA?
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2k
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Sorting dictionary values and getting sorted keys in new dictionary using Google Earth Engine
How can I sort a dictionary's keys in Earth Engine based on their values?
For example, I have such a dictionary defined in Earth Engine after some calculations and I want to sort that based on ...
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7
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2
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359
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Classifying raster layer by number of equal values in given area using QGIS
I am using QGIS 3.16.12 - Hannover. I have a binary raster layer which consists of 2 values, either 0 or 1 (in my screenshots, 0 = black, 1 = white). The 1 values are scattered throughout the layer in ...
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340
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Changing raster pixel values outside of polygon box using rioxarray
How do I change all raster pixel values outside of a polygon (keep the original values inside polygon) into a certain value?
I have passed through rioxarray clip() like below from this link:
...
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65
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Projecting raster changes the range of values
I am trying to project a 1 second DEM from GDA94 to UTM56 in ArcMap using the Project Raster tool. I tried different methods: bilinear, cubic, nearest neighbor. Nevertheless, the values of the output ...
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87
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MOD04_L2 data processing in r
i am new to using r, so i excuse in advance for asking basic question. I have been trying to convert MOD04_L2 data into GeoTIFF and extract value to a district shapefile in R. the coding seems to work ...
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46
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Adjusting pixel values to new pixel sum
I'm working with land use rasters in QGIS. For my application I have created rasters with pixels that have a fraction of 0-1 (for 0-100%) for a land use class. So for example in my settlement raster ...
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2
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271
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QGIS3 - Simple automation of QGIS output - turn values on/off & print out dozens of maps
I need to make a series of maps of a single location and make a single map for each value in the layer.
I have a layout I've created with borders, texts, north arrow, and everything, with the map, and ...
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145
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Reprojecting a raster results in larger raster values than the original raster values [duplicate]
When I reproject a raster in ArcMap using the project raster function (details in the image above) to change its X,Y coordinate system from North_America_1983_Transvers_Mercator to NAD_1983_Idaho_TM, ...
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117
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Tabulate intersection, but I need it with null values too, not just with matching intersect
I have problem with tabulate intersection tool (In ArcGIS - ArcMap 10.7.1). The number of data is 1298 with 500 m buffer. Then i have polygons, that I need to process. I run the tool, but get the ...
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3
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916
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Digitizing and adding attribute values to the points in QGIS
I want to build a digital terrain model from nautical charts. I need to capture the points where depth is indicated in the chart, and for each point, I must attribute the depth value. One by one, to ...
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2
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297
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Answers to be filled in by default with an expression doesn't work in QFIELD
I have set up a project in QGIS with default expressions which takes data from other fields previously filled in and automatically generates a value. It works fine when filling a form into QGIS but it ...
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2
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205
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How to add BC-dates (age of a continent)
I want to simulate continental drifts using the time tool of QGIS (V. 3.16.0). Turns out I can only insert certain dates into my attribute table. I can't even type in the date 0000-01-01 without ...
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2
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792
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Replacing all "NULL" values in multiple rows with "0"
I am looking for a way to replace all "NULL"-Values throughout multiple rows/ all "NULL"-Values in an attribute table. The table is from a SHP-File (shapefile).
Is there any easy ...
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37
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Python Code for deleting identical values from one column - ArcMap [closed]
I need Python code for deleting all identical values which are compared within one column.
As you can see in the image there are many identical values which I want to get rid of.
I tried the delete ...
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237
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QGIS Legend only with Raster Minimum and Maximum values
I want to have a mimim and maximum raster values in the legend but it appears to me a long list of all values how can I resume the legend minimum and maximum values:
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969
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How to create a Value Map widget type to select multiple values (checklist) from the dropdown?
I have a polygon layer that represents tree/shrub planting sites that were done. As part of the attribute table, I have fields representing things like tree density, species, soil work, tree size, etc....
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2k
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Reading raster values in points gives back a generator object instead of actual value
Given a raster TIF file and a point feature class in a geodatabase, I am trying to extract the values of the raster on the points and add them as a new column on the point feature class. I am using ...
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55
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Losing pixels values when counting by value
I have a script that calculates number of pixels with NDVI values that are higher than 0.3, 0.5 and 0.7.
My code runs with no errors, but it get value 0 and doesn't really count.
what can be the ...
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2
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1
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274
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Extracting pixel values in different bands for different points giving NAs and not pixel values
I am working with R statistics. And I am trying to extract pixel values for each point in each Landsat bands, however, I am just getting NAs instead of getting pixel values
Does anyone have any ...
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2
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669
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Deleting values less than 0.31 in NDVI raster layer in QGIS
In my research I have a Ndvi raster layer, and I want to delete the values corresponding to bare soil, which are those minor of 0.31. Therefore, I will obtain a new raster layer with those values ...
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605
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Exctracting values and their coordinates from a raster layer in QGIS?
I would like to extract the pixel value and coordinates of each of them from a ndvi raster layer. I don't have a point layer from where I can extract those values, as I read in other posts.
...
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273
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Interpolate the gaps among NDVI values [closed]
I want to calculate the Crop Water Requirements and for this I need NDVI values for a period of time.
Because I have Sentinel 2 images and the temporal resolution is 5 days, I need also the values ...
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2k
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Finding the minimum value of different columns in QGIS
I'll try to calculate the minimum value of four different columns in my QGIS table like:
The min. value would be 1,50286 in the first row.
Is there any expression or tool to find the minimum value ...
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62
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ArcMap 10.6: Is it possible to extract point values from points?
I've got three point shapes with different fields that I cannot seem to merge as I get ERROR 000229: cannot open 'name of shapefile'. Instead of solving this error, I wanted to try something different:...
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2k
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QGIS-Export Raster Values to a .csv file
I use a Raster, based on .png and .pgw file. (plans from a town)
The plans include information about where buildings are allowed to be built and maximum building height, ground elevation etc.
Now i ...
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1
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22
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Making the results from function a string [closed]
I am trying to get the features count from feature, then put it in a dictionary that I can call later:
ct_dict = dict()
...
fipsList = ['13245','06007']
for fip in fipsList:
mergedJoinCentroids =...
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841
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PostGIS: Change raster values depending on values from other raster
I have two rasters and I want to change all the values from "raster1" to 4, where they are larger than the values from "raster2" and to 0, where they are smaller.
So raster2 has only one value, which ...
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223
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Polygonizing distinct values using QGIS?
I am using QGIS 3.0.3 and I am trying to create simulated data through two sets random points distributed along two gradients of values (photo below). Using the raster calculator I created two ...
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649
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Null values being interpolates as 0 in QGIS
I have a file with data fields which I have imported as CSV. When I look at the Field Attribute Table, the empty fields appear clearly as NULL values. However when I interpolate the data, the NULL ...
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410
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Return a set of unique pixel values in a raster with PyQGIS? [closed]
I am trying to test whether a value exists in a raster against all the values present. I am using pyqgis (Python 2.7) in in QGIS 2.14. I have found a number of ways to get point location values and ...
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