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Questions tagged [distinct-values]

Use this tag for questions related to Distinct Values, i.e. values that are distinct/unique from the values in a collection.

632 questions
656
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34 answers

Java 8 Distinct by property

In Java 8 how can I filter a collection using the Stream API by checking the distinctness of a property of each object? For example I have a list of Person object and I want to remove people with the same name, persons.stream().distinct(); Will use…
RichK
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How to maintain a Unique List in Java?

How to create a list of unique/distinct objects (no duplicates) in Java? Right now I am using HashMap to do this as the key is overwritten and hence at the end we can get HashMap.getKeySet() which would be unique. But I am sure…
user1804287
118
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7 answers

List distinct values in a vector in R

How can I list the distinct values in a vector where the values are replicative? I mean, similarly to the following SQL statement: SELECT DISTINCT product_code FROM data
Mehper C. Palavuzlar
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12 answers

Counting unique / distinct values by group in a data frame

Let's say I have the following data frame: > myvec name order_no 1 Amy 12 2 Jack 14 3 Jack 16 4 Dave 11 5 Amy 12 6 Jack 16 7 Tom 19 8 Larry 22 9 Tom 19 10 Dave …
Mehper C. Palavuzlar
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59
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4 answers

select distinct items from a column in powershell

If I issue following command in PowerShell, I get a lot of rows back. PS C:\Users\benh> get-command CommandType Name ModuleName Definition ----------- ---- …
Ben H
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43
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2 answers

pyspark: count distinct over a window

I just tried doing a countDistinct over a window and got this error: AnalysisException: u'Distinct window functions are not supported: count(distinct color#1926) Is there a way to do a distinct count over a window in pyspark? Here's some example…
Bob Swain
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Spark DataFrame: count distinct values of every column

The question is pretty much in the title: Is there an efficient way to count the distinct values in every column in a DataFrame? The describe method provides only the count but not the distinct count, and I wonder if there is a a way to get the…
Rami
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6 answers

Selecting distinct 2 columns combination in mysql

I have a mysql table that looks like this: 1 value1 value2 3534 2 value1 value1 8456 3 value1 value2 3566 4 value1 value3 7345 5 value2 value3 6734 I need a query to select all the rows with distinct column 2…
James Harzs
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Get distinct list between two lists in C#

I have two lists of strings. How do I get the list of distinct values between them or remove the second list elements from the first list? List list1 = { "see","you","live"} List list2 = { "see"} The result should be…
kartal
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get Distinct Values with Sorted Data

I need a Query to get distinct keys with sorted on basis of score in Mongodb 1.6.5 I have records Like {key ="SAGAR" score =16 note ="test1" } {key ="VARPE" score =17 note ="test1" } {key ="SAGAR" score =16 note ="test2" } {key ="VARPE" score…
Sagar Varpe
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R: How do I choose which row dplyr::distinct() keeps based on a value in another variable?

The real life problem: I have subjects with MRI scan data. Some of which have been scanned multiple times (separate rows). Some of those were scanned under different protocols each time. I want to keep all unique rows by subject ID, and if a subject…
Bart
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Creating distinct list from existing list in Java 7 and 8?

If I have: List listInts = { 1, 1, 3, 77, 2, 19, 77, 123, 14, 123... } in Java what is an efficient way of creating a List listDistinctInts containing only the distinct values from listInts? My immediate thought is to create a…
Matt Coubrough
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How to generate list of unique random floats in Python

I know that there are easy ways to generate lists of unique random integers (e.g. random.sample(range(1, 100), 10)). I wonder whether there is some better way of generating a list of unique random floats, apart from writing a function that acts like…
Simon
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How to use Distinct function in influxDB

I am using influx DB and issuing command, SELECT * FROM interface Below is the out put- interface time element path value 2016-08-24T21:22:16.7080877Z …
Ammad
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Trying to sum distinct values SQL

I'm having trouble coming up with a value for a cell in SSRS, which should be a sum of distinct values. I have a SSRS report that looks similar to the below screenshot: I'm having trouble getting the value in red ($11.25). I basically need to sum…
kyle_13
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