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Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
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Inserting multiple rows in a single SQL query? [duplicate]
...much better methods as seen in the other answers.
You can use INSERT with SELECT UNION ALL:
INSERT INTO MyTable (FirstCol, SecondCol)
SELECT 'First' ,1
UNION ALL
SELECT 'Second' ,2
UNION ALL
SELECT 'Third' ,3
...
Only for small datasets though, which should be fine for your 4 rec...
Is it possible for git-merge to ignore line-ending differences?
...e.autoCRLF=false
Test that, when two lines are identical (but their eol chars), both DiffMerge or KDiff3 will ignore those line during a merge.
DOS script (note: the dos2unix command comes from here, and is used to simulate a Unix eol-style. That command has been copied in the directory mentione...
What is the difference between square brackets and parentheses in a regex?
...nt, you would code (?:7|8|9) to make it a non capturing group.
[abc] is a "character class" that means "any character from a,b or c" (a character class may use ranges, e.g. [a-d] = [abcd])
The reason these regexes are similar is that a character class is a shorthand for an "or" (but only for singl...
How to identify all stored procedures referring a particular table
...
SELECT Name
FROM sys.procedures
WHERE OBJECT_DEFINITION(OBJECT_ID) LIKE '%TableNameOrWhatever%'
BTW -- here is a handy resource for this type of question: Querying the SQL Server System Catalog FAQ
...
Default implementation for Object.GetHashCode()
...sually more interested in whether a string containing the same sequence of characters has already been added. That's why string overrides GetHashCode. On the other hand, suppose you want to keep a count of how many times various controls process Paint events. You could use a Dictionary<Object,...
What does jquery $ actually return?
...
From Rick Strahl's description:
The jQuery Object: The Wrapped Set:
Selectors return a jQuery object known
as the "wrapped set," which is an
array-like structure that contains all
the selected DOM elements. You can
iterate over the wrapped set like an
array or access individual elem...
Postgres: Distinct but only for one column
...h names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
3 Ans...
Getting current device language in iOS?
... will actually return the current region of the device - not the currently selected language. These are often one and the same. However, if I am in North America and I set my language to Japanese, my region will still be English (United States). In order to retrieve the currently selected language, ...
How can I return pivot table output in MySQL?
...OUP BY.
The basic SQL providing this pivot can look something like this:
SELECT P.`company_name`,
COUNT(
CASE
WHEN P.`action`='EMAIL'
THEN 1
ELSE NULL
END
) AS 'EMAIL',
COUNT(
CASE
WHEN P.`action`='PRINT' AND...