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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...
Get lengths of a list in a jinja2 template
... Thanks @AlexMartelli. In addition we could use inline syntax like {{ form.select_field(size=5 if form.select_field.choices|count > 5 else form.select_field.choices|count) }}
– Filipe Bezerra de Sousa
Jun 28 at 23:52
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What is the difference between NULL, '\0' and 0?
...e appear to be differences between various values of zero -- NULL , NUL and 0 .
11 Answers
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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 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'
...
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...
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 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...
C/C++ include header file order
...ed without prerequisites (terminus technicus: header is "self-contained"). And the rest just seems to flow logically from there.
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How to debug template binding errors for KnockoutJS?
...he first input box of the second contact (the one with
the text 'Sensei').
Select 'Inspect element'. The Chrome Developer Toolbar will open.
Open the JavaScript Console window. You can access the console by
clicking the >= icon in the bottom-left of the Chrome Developer
Toolbar, or by opening the...