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python pandas remove duplicate columns
...,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
Finally, df.loc[:,[True,True,False]] selects only the...
What is the difference between “AS” and “IS” in an Oracle stored procedure?
...lied to make your code more readable:
FUNCTION f IS ...
CREATE VIEW v AS SELECT ...
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How do you track record relations in NoSQL?
...(A .NET based NoSQL Database with SQL support) your queries will be like
SELECT * FROM Comments WHERE userid = ‘That user’;
SELECT * FROM Comments WHERE pageid = ‘That user’;
SELECT * FROM Comments WHERE post-time > DateTime('2016, 1, 1');
SELECT * FROM Page WHERE tag = 'kendo'
...
Using Emacs to recursively find and replace in text files not already open
...files, type D to close them all.
Step-by-Step Guide for Emacs Beginners
Select Target Files
Start emacs by typing “emacs” in the command line interface prompt. (Or, double click the Emacs icon if you are in a Graphics User Interface environment)
Selecting Files in a Directory
First you nee...
How do I use vim registers?
...
@dotancohen Technically it's called PRIMARY selection, but I guess "mouse higlight" is easier for people to get :)
– kyrias
Nov 26 '13 at 16:45
...
OrderBy descending in Lambda expression?
... orderby person.Name descending, person.Age descending
select person.Name;
is equivalent to:
var query = people.OrderByDescending(person => person.Name)
.ThenByDescending(person => person.Age)
.Select(person => person.Name);
...
How to get the Android device's primary e-mail address
...T_DIRECTORY),
ProfileQuery.PROJECTION,
// Select only email addresses.
ContactsContract.Contacts.Data.MIMETYPE + " = ?",
new String[]{ContactsContract.CommonDataKinds.Email.CONTENT_ITEM_TYPE},
// Show primary email add...
How to call Stored Procedure in Entity Framework 6 (Code-First)?
...Campaign]
@ClientId int
AS
BEGIN
SET NOCOUNT ON;
SELECT AgeGroup, Gender, Payout
FROM IntegrationResult
WHERE ClientId = @ClientId
END
create a class that looks like:
public class ResultForCampaign
{
public string AgeGroup { get; set; }
...
Difference between clustered and nonclustered index [duplicate]
...a completely different object within the table that contains the column(s) selected for indexing and a pointer back to the table’s rows containing the data. It is like an index in the last pages of a book, where keywords are sorted and contain the page number to the material of the book for faster...
How do I create a list of random numbers without duplicates?
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This will return a list of 10 numbers selected from the range 0 to 99, without duplicates.
import random
random.sample(range(100), 10)
With reference to your specific code example, you probably want to read all the lines from the file once and then select rand...