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Questions tagged [grouping]

The process of grouping entities into collections of associated elements.

Grouping is a form of hierarchical knowledge representation, similar to mind mapping, concept mapping and argument mapping, all of which need to observe at least some of the principles of grouping.

SQL Server - Indicates whether a specified column expression in a GROUP BY list is aggregated or not. Read more about this

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Grouping by a Map value in Java 8 using streams

I have a List of Map that i want to group it by the key nom using java streams. [ { "dateDebut": "2018-07-01T00:00:00.000+0000", "nom": "Julien Mannone", "etat": "Impayé" }, { "dateDebut":…
Wassim Makni
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How to add sequence number for groups in a SQL query without temp tables

I've created a complex search query in SQL 2008 that returns data sorted by groups, and the query itself has paging and sorting functions in it, but rather than returning a set number of records based on the paging options, it needs to return a set…
Jacob
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pandas grouper vs time grouper

The new pandas version deprecates the TimeGrouper, so we should use the regular Grouper. The old code: df['column_name'].groupby(pd.TimeGrouper("M")).mean().plot() works fine in the old version of pandas. However, none…
Georg Heiler
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Grouping and counting to get a closerate

I want to count per country the number of times the status is open and the number of times the status is closed. Then calculate the closerate per country. Data: customer <- c(1,2,3,4,5,6,7,8,9) country <- c('BE', 'NL',…
Rhulsb
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d3 accessing nested data in grouped bar chart

I'm building a grouped bar chart by nesting a .csv file. The chart will also be viewable as a line chart, so I want a nesting structure that suits the line object. My original .csv looks like…
tgerard
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Group by identity in Ruby

How does Ruby's group_by() method group an array by the identity (or rather self) of its elements? a = 'abccac'.chars # => ["a", "b", "c", "c", "a", "c"] a.group_by(&:???) # should produce... # { "a" => ["a", "a"], # "b" => ["b"], # "c" =>…
sschmeck
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SQL: Is it possible to 'group by' according to 'like' function's results?

I am using Oracle SQL and I want to group some different rows that 'like' function results. To elaborate with an example: Let's assume I have a table MESA with one of the columns is a huge string. And I am counting the number of rows matching…
someone
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Get grouped comma separated values with linq

I would like a third column "items" with the values that are grouped. var dic = new Dictionary(); dic.Add("a", 1); dic.Add("b", 1); dic.Add("c", 2); dic.Add("d", 3); var dCounts = (from i in dic group i by i.Value into g …
Micah B.
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Grouping Multiple Annotations

I have java 1.7. Is there any way to group multiple annotations to single one. So that i annotate with single annotation and gets all the properties of all grouped multiple annotations. I want to avoid multiple annotation lines repeated every…
Rahul
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Count, Sort and Group-By in Powershell

Are there any cool cmdlets that will help me do the following? I want something in Powershell that is as simple as doing the same in SQL: select RootElementName , count(*) from Table group by RootElementName order by RootElementName I'm all XML…
NealWalters
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Java 8 grouping by from one-to-many

I want to learn how to use the Java 8 syntax with streams and got a bit stuck. It's easy enough to groupingBy when you have one key for every value. But what if I have a List of keys for every value and still want to categorise them with groupingBy?…
Mikael Grev
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PHP splitting arrays into groups based on equal values

I have an Array containing arrays with 2 values, the first one is the Number of the Author the second is his Affiliation. Array ( [0] => Array ( [0] => 2 [1] => Department of General Chemistry ) [1] =>…
user2419708
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How to get length of current group in data.table grouping?

I know this can be achieved with other packages, but I'm trying to do it in data.table (as it seems to be the fastest for grouping). library(data.table) dt = data.table(a=c(1,2,2,3)) dt[,length(a),by=a] results in a V1 1: 1 1 2: 2 1 3: 3 …
jamborta
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SQL Group By - Generate multiple aggregate columns from single column

I would like to group by Company & Date and generate count columns for 2 separate values (Flag=Y and Flag=N). Input table looks like this: Company Date Flag ------- ------- ----- 001 201201 Y 001 201201 N 001 201202 N 001 …
Thracian
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awk extract multiple groups from each line

How do I perform action on all matching groups when the pattern matches multiple times in a line? To illustrate, I want to search for /Hello! (\d+)/ and use the numbers, for example, print them out or sum them, so for input abcHello! 200 300 Hello!…
Adrian Panasiuk
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