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Replace only the unll values in one field with another [closed]

I have a few thousand records that have different field names for their "Facility names" (plant names, etc) I want to use calculate field or really any method to say that (in pseudo code) ...
Teckert87's user avatar
2 votes
2 answers
77 views

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 ...
Chavdar Kirilov's user avatar
3 votes
1 answer
213 views

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 ...
Dia's user avatar
  • 31
0 votes
1 answer
30 views

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 ...
minyahil tilahun's user avatar
0 votes
0 answers
22 views

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 ...
A_Y's user avatar
  • 91
5 votes
1 answer
191 views

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 ...
Ingrid Ingravida's user avatar
3 votes
1 answer
90 views

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 ...
Ingrid Ingravida's user avatar
3 votes
1 answer
217 views

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 ...
Horizen's user avatar
  • 567
1 vote
1 answer
84 views

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 ...
GIS Noh's user avatar
  • 321
1 vote
0 answers
113 views

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 ...
paula's user avatar
  • 11
4 votes
1 answer
347 views

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 ...
Bertram's user avatar
  • 483
1 vote
1 answer
487 views

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 ...
Marek's user avatar
  • 537
-2 votes
2 answers
331 views

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 ...
coral's user avatar
  • 81
1 vote
1 answer
121 views

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, ...
GeoEth's user avatar
  • 347
2 votes
1 answer
661 views

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 ...
Sickboy's user avatar
  • 167
1 vote
0 answers
20 views

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?
sophie's user avatar
  • 11
3 votes
1 answer
429 views

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 ...
Nikos's user avatar
  • 1,033
0 votes
0 answers
134 views

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 ...
Just_4n0th3r_Pr0gr4mm3r's user avatar
1 vote
1 answer
4k views

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(&...
Fabio Castelli's user avatar
0 votes
0 answers
37 views

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 ...
javir Ib's user avatar
0 votes
0 answers
107 views

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 ...
Robbie-G95's user avatar
0 votes
1 answer
116 views

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?
Muyao's user avatar
  • 3
1 vote
1 answer
3k views

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 ...
Solmaz's user avatar
  • 149
7 votes
2 answers
397 views

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 ...
Snowy's user avatar
  • 113
0 votes
0 answers
414 views

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: ...
Happier's user avatar
  • 67
0 votes
0 answers
81 views

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 ...
novice here's user avatar
0 votes
0 answers
112 views

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 ...
hina yaqub's user avatar
0 votes
0 answers
57 views

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 ...
flowerts's user avatar
2 votes
1 answer
347 views

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 ...
Mike P's user avatar
  • 29
1 vote
1 answer
171 views

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, ...
Atiqullah Atif's user avatar
0 votes
0 answers
128 views

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 ...
pipi94's user avatar
  • 1
2 votes
3 answers
1k views

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 ...
Carlos Augusto Frana Schettini's user avatar
1 vote
2 answers
378 views

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 ...
Serggg182's user avatar
  • 621
1 vote
2 answers
240 views

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 ...
DonMeles's user avatar
4 votes
2 answers
989 views

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 ...
Corninski's user avatar
-2 votes
1 answer
43 views

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 ...
Chris's user avatar
  • 11
1 vote
1 answer
295 views

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:
Gab's user avatar
  • 403
3 votes
1 answer
1k views

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....
Robert's user avatar
  • 43
3 votes
2 answers
2k views

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 ...
Pitrako Junior's user avatar
1 vote
1 answer
56 views

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 ...
ReutKeller's user avatar
  • 2,149
2 votes
1 answer
294 views

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 ...
Lisa's user avatar
  • 41
0 votes
2 answers
832 views

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 ...
Ange's user avatar
  • 63
1 vote
1 answer
788 views

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. ...
Ange's user avatar
  • 63
0 votes
1 answer
342 views

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 ...
Cristina Mihalache's user avatar
8 votes
2 answers
2k views

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 ...
Walther's user avatar
  • 183
0 votes
1 answer
64 views

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:...
Renée's user avatar
  • 351
1 vote
1 answer
2k views

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 ...
Daniel_B's user avatar
0 votes
1 answer
22 views

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 =...
gwydion93's user avatar
  • 1,903
3 votes
2 answers
901 views

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 ...
blueJay's user avatar
  • 31
1 vote
0 answers
226 views

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 ...
Arthur Scully's user avatar