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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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Minimum-Waste Print Job Grouping Algorithm?

I work at a publishing house and I am setting up one of our presses for "ganging", in other words, printing multiple jobs simultaneously. Given that different print jobs can have different quantities, and anywhere from 1 to 20 jobs might need to be…
Matt Mc
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Error incrementing crosstab dataset

I have a data source that is composed of object { groupName, rowName, colName, value }. I'm trying to put the fields row,col,val in a crosstab, separated by group [the group has headers]. A collection of the data objects is being stored as the main…
monksy
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Use Collectors.groupingby to create a map to a set

I know how to create a Map> , using Collectors.groupingBy: Map> listMap = items.stream().collect(Collectors.groupingBy(s->s.key)); How would I modify that code to create Map>? Or can I not do it using stream…
simonalexander2005
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Create string ranges from sorted array of integers

I have following sorted array of numbers (they can repeat e.g 21) let a = [1,2,3,4,7,8,12,15,21,21,22,23] And want to get following (sorted) array of strings with ranges let r =["1-4","7-8","12","15","21-23"] for consecutive numbers…
Kamil Kiełczewski
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Java Stream GroupingBy collect in custom object

I have a Temperature Class class Temperature { double minTemp; double maxTemp; String city; String country; } I have another class that maintains a collection of Temperature class Temperatures { List…
user2578909
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Golang: group and sum slice of structs

I come from the .NET world where I had LINQ so I could do in-memory queries like the one we usually see in SQL. I have a slice of this structure I want to group by 8 fields, and then sum another integer field. Something like: type Register struct { …
Marcos
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Algorithm to match preferred partners into groups of three

What's a good algorithm to solve this problem? I have three groups of people - group A, group B, and group C. There are the same number of people in each group. They each have a list of people in the other groups that they're willing to work with. I…
Claudiu
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What does n=n( ) mean in R?

The other day I was reading the following lines in R and I don't understand what the %>% and summarise(n=n()) and summarise(total=n()) meant. I understand the group_by and ungroup methods though. Can someone help out? There isn't any documentation…
Kashif
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$week function and first day of week in aggregation

I use $project operator to extract week part from Date, then do grouping by weeks in aggregation pipeline: { $project: { year: { $year: [ "$datetime" ] }, week: { $week: [ "$datetime" ] }, .... } }, .... { $group: { _id: { …
Volodymyr Metlyakov
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Java : replacing text URL with clickable HTML link

I am trying to do some stuff with replacing String containing some URL to a browser compatible linked URL. My initial String looks like this : "hello, i'm some text with an url like http://www.the-url.com/ and I need to have an hypertext link…
Dough
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Group by Sum in Excel

Let's assume that I have the following table in Excel A B Item quantity_sold A 3 A 4 A 1 B 5 B 2 D 12 C 3 C 7 C 8 and I need to sum up quantity_sold grouped by Item and print the results on the adjacent…
Ahmadov
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ggplot multiple grouping bar

I would like to know how to get 9 grouping bar plot (3x3) together. My CSV: data <- read.csv("http://pastebin.com/raw.php?i=6pArn8GL", sep = ";") The 9 plots should be grouped according "Type" A to I. Then each grouped bar plot should have the…
S12000
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Doxygen: How to include an element in multiple groups

The Doxygen documentation says that \ingroup can be used to add an entity to multiple groups: \ingroup ( [ ]) The problem is that I tried it and Doxygen adds the entitiy to just the last group in the group list.…
user2432986
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Nested aggregate functions with grouping in postgresql

I'm trying to get an average of sums using nested aggregate functions and grouping. What I would want to do is: SELECT AVG(SUM(x) GROUP BY y) WHERE ... GROUP BY ...; That is, for each row returned, I want one of the fields to be an average of sums,…
ferson2020
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Datatables row grouping - how to add rowcount per group and expand/collapse all

I am using Datatables Collapsible/Expandable Grouping. http://jquery-datatables-row-grouping.googlecode.com/svn/trunk/collapsibleGroups.html I have configured it so that all groups collapsed in the initial view. I would really like to add the…
lbriquet
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