Questions tagged [concatenation]

In formal language theory and computer programming, string concatenation is the operation of joining character strings end-to-end. For example, the concatenation of "snow" and "ball" is "snowball". In some but not all formalisations of concatenation theory, also called string theory, string concatenation is a primitive notion.

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4
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2answers
97 views

Combining columns in attribute table

How can I merge columns in attribute table with / as delimeters?
4
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1answer
61 views

Concat fields which are not NULL

I am using the concat function in QGIS 3.16.6 on Mac. I want to join several cell values into one new cell. With the concat function it is ignoring cells with NULL but it doesn't separate the cell ...
3
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2answers
102 views

Click features & aggregate unique attributes only (QGIS)

In QGIS 3.16: the "merge feature attributes" function (on the advanced digitizing toolbar) allows merging the attributes of selected features by either 1) selecting which feature to keep the ...
4
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1answer
74 views

'Evaluation error' when using Aggregate tool in QGIS

In QGIS 3.16. I am using the Aggregate function to reduce the number of features in a layer. I am grouping by one field and I want to concatenate the others. My actual data table is fairly large and ...
3
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2answers
140 views

Area of each polygon that intersects another layer and total area of intersections in QGIS

I have two layers: 'A' (orange) and 'B' (purple). Using a Virtual Layer and group_concat I am able to list the polygons in layer 'B' that intersect with those in layer 'A' thanks to @Jesse McMillan's ...
4
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1answer
104 views

Merge adjacent polygons & concatenate attribute values (QGIS)

In QGIS 3.16. I have a layer of 1000+ polygons, many of which are adjacent (touching, overlapping, or one completely inside another). If all of the adjacent polygons are merged, I will end up with ...
3
votes
1answer
62 views

adding x and y into single column in QGIS

I have always use the field calculator to retrieve my x and y coords ($x, $y), but this ends up with 2 separate columns, which I then have to manually concatenate. Is there a way to do this easily ...
1
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1answer
63 views

How to iterate through various layers and export each with an additional word to its file name

I'm batch dissolving some layers in QGIS and want to save each dissolved shapefile as <layername>_dissolved.shp. I'm using a for-loop but it just shows raise QgsProcessingException(msg) _core....
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0answers
47 views

QGIS: spatialite incorrect string concatenation when loading layers

I am trying to draw some polygons in spatialite using the DB Manager in QGIS. However select 1 as id, st_geomfromtext('POLYGON((0 0,0 '||random()||','||random()||' '||random()||','||random()||' 0,0 0))...
4
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1answer
52 views

Dropping duplicate strings when using group_concat in Virtual Layer

When using Virtual Layer to group_concat() a string field, the result would contain duplicates string. For example, here's a polygon layer "city_lot" with "land_use" and "...
2
votes
1answer
72 views

StopIteration: iteration not started

I'm trying to update a given field in this case the last one of the table by concatenating all values in the row excepting null values or '' values. So far when execute the code until line: print (...
2
votes
1answer
58 views

Concatenating fields into a new field-QGIS

I'm not sure what I'm missing here. I'm trying to use the field calculator to concatenate multiple fields into one new. All fields are identified as strings. My expression: concatenate( "Building" ...
3
votes
1answer
3k views

Merging a geodataframe and pandas dataframe based on a column

I have a simple geopandas dataframe that includes geometry and a column called 'MUKEY': merged_spatial_df.head() I want to merge it to a tabular (.csv) pandas dataframe (which also has a column ...
3
votes
1answer
215 views

Get Attributes from 1:n relation in QGIS as Expression to use in Atlas

I need to set up way signs for something like a "hiking-GIS". In the first step I made a network analysis (using QNEAT3) to find the distance from the signs ("Way Signs") to the available destinations ...
4
votes
1answer
360 views

Layout expression for getting all features of layer within the current map view in QGIS 3?

In a map layout template, I want to insert an expression which gets all feature's names of a certain layer, which are contained in the current layout's view/extent. Is there a way to get an aggregate ...
2
votes
1answer
345 views

Add column in QGIS

Is it possible to add a column in the attribute table in QGIS that is a concatenation of two other columns? For example I have a column "Genus" and a column "Species" and I would like to create a ...
4
votes
2answers
699 views

Concatenate attributes ignoring NULL/missing values with FME

I've got a table with different attributes (named "source:geommetry", "source:name", "source:power"...) I'd like to concatenate to one attribute named "source_all" using FME Desktop. A blank space is ...
3
votes
1answer
289 views

QGIS 2.18 label by expression concatenate field strings

For a building layer I have an attribute table with several fields for the building type where data was entered with a manually created form using checkboxes. Example: Production: 1 = (yes), 0 = (no) ...
0
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1answer
97 views

Concatenate five fields where some may be NULL

I have a trench containing five types of ducts. I have created fields the trenches: Type1, Type2, Type3, ... The values in each field are the numbers of each type of duct that the trench contains. ...
1
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1answer
158 views

Syntax error when using concat function

I created a field to display the whole route of several photos in a point layer in order to be able to visualize them on the map. I try to do so by using this expression: concat('C:\Users\DIDAC\...
1
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0answers
61 views

I want to combine or merge rasters

I am combining many rasters using a "barcode" that describes attributes for each cell. Combine works on integer values: I combine multiple layers using "combine" tool, then create the bar code by ...
1
vote
1answer
636 views

Simple Field Calculation With No Results in ArcGIS Pro?

I have a grid in ArcGIS Pro that I've named the X and Y axis (in separate columns) and am now trying to do a field calculation on the total grid name (I've tried using both single and double quotes. I'...
2
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4answers
2k views

Concatenating address fields with possible blank or null values in fields using Python parser?

The following Python code is what I have already tried in field calculator of ArcMap 10.5.1: Pre-Logic Script Code: def ConcatAddr(!JOIN_KEY!) val = "" if !Address! <> val ...
1
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1answer
72 views

Copying specific folder into subfolders with ArcPy?

I'm working on Arcgis 10.5 and I am trying to achieve this: On my script, I want to make folders and subfolder, and also I want to copy one specific folder into several subfolders at the same time. ...
1
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3answers
661 views

Concatenating two columns in ArcGIS 10.2.1: “no records within table”?

I am trying to merge two text columns (consisting of 2 digit and 3 digit numbers respectively) into one in ArcGIS 10.2.1 desktop version, but unable to do so. I have added a new field and kept it as ...
1
vote
1answer
333 views

Concatenate Label Values Fails to Calculate Aggregate

I'm trying to do what seems like a very simple operation (It's SUPER easy in ArcMap...). I'm kind of a novice with QGIS, so it's probably something really simple that I'm doing incorrectly. The ...
2
votes
1answer
2k views

Concatenating string with space

I am adding a number of strings together to create a linestring but as such I need spaces between the initial XY values and the end XY values, plus a comma in between the two halves. Should result in ...
3
votes
3answers
3k views

Concatenating strings from two fields using Python in ArcMap Field Calculator?

I'm new to Python scripting and I don't understand what is wrong with this code. I want to concatenate the string values from GRID1MIL and GRID100K. I've created a text column MGRS to begin with. I ...
0
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1answer
127 views

Cannot define output with Concatenated path

I am working on a series of geoprocessing tasks and trying to define the output through the concatenation of folders, a geodatabase, and finally a raster dataset. Each way I try it I receive an error ...
5
votes
3answers
1k views

Listing IDs of polygons within another polygon in the Attribute table

I have two polygon shapefiles in QGIS. I would like to have the polygon "ID"s of 'B' listed in the attribute table of 'A' for the case that they overlap. As a demonstration: I tried ...
1
vote
1answer
225 views

Regrouping concat labels with overlapping intersecting geometries in QGIS

All the fields i want to show on the map are in the same layer. All the labels have to be showed on the map. But the concentration is high. So i would like to concat the labels when geometries are ...
1
vote
1answer
3k views

How to concatenate string and noneType object

My issue is: I can't concatenate string and noneType object. Some attribute values are empty. It follows that label isn't displayed. What is the solution? def FindLabel ( [CONTENU], [...
0
votes
1answer
182 views

Using cursor to populate a new field by concatenating existing fields

I have a question for a current assignment that requires me to write a script that will add a new field to a feature class and then use a cursor to populate the new field by concatenating five other ...
3
votes
1answer
29 views

Find unique ZIP codes and add to field

I have multiple values in a table with the same CODE(Name) and each one has a ZIP. How to find all of the unique ZIP codes and add them to a field. Here is an example of the result I am looking for: ...
0
votes
0answers
138 views

Spatial join with concatenation of results

I've two polygon layers which I would make a spatial join. The objective is to transport a specific code from layer A (Municipality) to layer B (Issues) using like a concatenate function, in this way ...
1
vote
0answers
42 views

QGIS: Join by Location: Option to retain all attributes of spatially related objects of my join layer [duplicate]

I am facing the problem that I want to join the attributes from one specific column of ALL intersecting features from my join layer to my target layer in case of an intersection (1:n relationship) ...
4
votes
2answers
654 views

Concatenating two fields (type double) into single field?

In ArcGIS 10.3 using the field calculator, I'm trying to concatenate a census tract field (double) with a census block field (double) into a single field that has the two values separated by a decimal ...
2
votes
2answers
501 views

Concatenate geospatial pdfs

I am looking for a simple way to concatenate one geospatial pdf (with multiple layers in a single image) and regular pdf. I have tried tools such as pdfunite, pdftk and pdfconcat, without success. The ...
5
votes
5answers
11k views

How to combine text and integers in a string field?

I have field with numbers in it (field type: double, number format: numeric) and I need to create a new field and put text in front of the numbers. I know that I need to add a new string field, but ...
19
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5answers
28k views

Concatenating fields in field calculator of QGIS?

Is there a way to concatenate fields in field calculator of QGIS? (e.g. hectares + ' ha')