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How to pad zeroes to a string?
...
Strings:
>>> n = '4'
>>> print(n.zfill(3))
004
And for numbers:
>>> n = 4
>>> print(f'{n:03}') # Preferred method, python >= 3.6
004
>>> print('%03d' % n)
004
>>> print(format(n, '03')) # python >= 2.6
004
>>> print('{0:...
How do I perform an IF…THEN in an SQL SELECT?
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The CASE statement is the closest to IF in SQL and is supported on all versions of SQL Server.
SELECT CAST(
CASE
WHEN Obsolete = 'N' or InStock = 'Y'
THEN 1
ELSE 0
END AS bit) as Saleable,...
How to plot two histograms together in R?
I am using R and I have two data frames: carrots and cucumbers. Each data frame has a single numeric column which lists the length of all measured carrots (total: 100k carrots) and cucumbers (total: 50k cucumbers).
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Setting the selected value on a Django forms.ChoiceField
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the tuples represent (value, label) pairs for the options and you want to specify the initial value - so the '3' refers to the first item.
– Tom
Oct 29 '17 at 10:19
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BaseException.message deprecated in Python 2.6
...- almost no coding needed
Just inherit your exception class from Exception and pass the message as the first parameter to the constructor
Example:
class MyException(Exception):
"""My documentation"""
try:
raise MyException('my detailed description')
except MyException as my:
print my # ...
How to concatenate properties from multiple JavaScript objects
... many modern browsers but not yet all of them. Use a transpiler like Babel and Traceur to generate backwards-compatible ES5 JavaScript.
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Is std::vector copying the objects with a push_back?
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Yes, std::vector<T>::push_back() creates a copy of the argument and stores it in the vector. If you want to store pointers to objects in your vector, create a std::vector<whatever*> instead of std::vector<whatever>.
However, you need to make sure that the objects referenced...
Portable way to get file size (in bytes) in shell?
...at --format="%s" FILE , but Solaris I have access to doesn't have stat command. What should I use then?
14 Answers
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Static method in a generic class?
...fields. The class's type parameters are only in scope for instance methods and instance fields. For static fields and static methods, they are shared among all instances of the class, even instances of different type parameters, so obviously they cannot depend on a particular type parameter.
It doe...
Shell Script: Execute a python program from within a shell script
...job.sh, put this
#!/bin/sh
python python_script.py
Execute this command to make the script runnable for you : chmod u+x job.sh
Run it : ./job.sh
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