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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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Producing a new line in XSLT
...aps in csv) you can output something like the following:
<xsl:value-of select="concat(elem1,elem2,elem3,$newline)" />
I've used this technique when outputting sql from xml input. In fact, I tend to create variables for commas, quotes and newlines.
...
Linq to SQL how to do “where [column] in (list of values)”
...CodeData>()
where codeIDs.Contains(codeData.CodeId)
select codeData;
But you might as well do that in dot notation:
var foo = channel.AsQueryable<CodeData>()
.Where(codeData => codeIDs.Contains(codeData.CodeId));
...
What's the best way to join on the same table twice?
...tiple times or using subqueries etc.
I would just clean things up a bit:
SELECT t.PhoneNumber1, t.PhoneNumber2,
t1.SomeOtherFieldForPhone1, t2.someOtherFieldForPhone2
FROM Table1 t
JOIN Table2 t1 ON t1.PhoneNumber = t.PhoneNumber1
JOIN Table2 t2 ON t2.PhoneNumber = t.PhoneNumber2
What i did:...
Selecting the first “n” items with jQuery
With Jquery, I need to select just the first "n" items from the page, for example the first 20 links instead of selecting all of them with the usual
...
How to format all Java files in an Eclipse project at one time?
...
Right click on the project root and select Source -> Format. This should work for at least version 3.8.1. and above.
If the above does not work, you're probably using an older Eclipse-version. In such case you can select your Source Folders by clicking on t...
How do I add a foreign key to an existing SQLite table?
...n step 8 below. One way to
do this is to run a query like the following: SELECT type, sql FROM
sqlite_master WHERE tbl_name='X'.
Use CREATE TABLE to construct a new table "new_X" that is in the
desired revised format of table X. Make sure that the name "new_X"
does not collide with any exi...
JavaScript get clipboard data on paste event (Cross browser)
...vent using a keypress event handler
In that handler, save the current user selection, add a textarea element off-screen (say at left -1000px) to the document, turn designMode off and call focus() on the textarea, thus moving the caret and effectively redirecting the paste
Set a very brief timer (say...
How to avoid mysql 'Deadlock found when trying to get lock; try restarting transaction'
...now() - INTERVAL 900 SECOND
To
DELETE FROM onlineusers
WHERE id IN (
SELECT id FROM onlineusers
WHERE datetime <= now() - INTERVAL 900 SECOND
ORDER BY id
) u;
Another thing to keep in mind is that mysql documentation suggest that in case of a deadlock the client should retry autom...
How to get CSS to select ID that begins with a string (not in Javascript)?
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The specificity of this type of selector is very low
– nuander
Sep 3 '15 at 21:24
3
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