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How to select the row with the maximum value in each group

In a dataset with multiple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset: ...
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Similar to jQuery .closest() but traversing descendants?

... These examples all select depth-first descendants, not breadth-first, so these can't be used to solve the original question. In my testing they all returned the first span, not the second. – JrBaconCheez M...
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C programming in Visual Studio

...project (not for the solution), expand Configuration Properties, C/C++ and select Advanced. Change the Compile As setting to Compile as C Code (/TC). https://docs.microsoft.com/en-us/cpp/ide/visual-cpp-project-types?view=vs-2017 ...
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Exit single-user mode

...tabase in MULTI_USER mode. USE master GO DECLARE @kill varchar(max) = ''; SELECT @kill = @kill + 'KILL ' + CONVERT(varchar(10), spid) + '; ' FROM master..sysprocesses WHERE spid > 50 AND dbid = DB_ID('<Your_DB_Name>') EXEC(@kill); GO SET DEADLOCK_PRIORITY HIGH ALTER DATABASE [<Your_DB...
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Selecting with complex criteria from pandas.DataFrame

...se pandas it has some built in functions for comparison. So if you want to select values of "A" that are met by the conditions of "B" and "C" (assuming you want back a DataFrame pandas object) df[['A']][df.B.gt(50) & df.C.ne(900)] df[['A']] will give you back column A in DataFrame format. pan...
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How to get the index of an element in an IEnumerable?

... extensions with overloads like Select((x, i) => ...) seem to imply that these indexes should exist – Michael Mar 19 '14 at 16:05 ...
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How to do a join in linq to sql with method syntax?

...eOtherClass on sc.Property1 equals soc.Property2 select new { SomeClass = sc, SomeOtherClass = soc }; Would be equivalent to: var result = enumerableOfSomeClass .Join(enumerableOfSomeOtherClass, sc => sc.Property1, soc => soc.Property2, ...
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PostgreSQL: Show tables in PostgreSQL

...a: \dt Programmatically (or from the psql interface too, of course): SELECT * FROM pg_catalog.pg_tables; The system tables live in the pg_catalog database. share | improve this answer ...
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How to set auto increment primary key in PostgreSQL?

...able(moobars,foobars) values('worldwide interblag','2012-05-02') Step 3, select * from your table: el@voyager$ psql -U pgadmin -d kurz_prod -c "select * from epictable" Step 4, interpret the output: mytable_key | moobars | foobars -------------+-----------------------+------...
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Can I create a One-Time-Use Function in a Script or Stored Procedure?

... create temp stored procedures like: create procedure #mytemp as begin select getdate() into #mytemptable; end in an SQL script, but not functions. You could have the proc store it's result in a temp table though, then use that information later in the script .. ...