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What is the difference between a mutable and immutable string in C#?
...ects themselves could change, and the data structure would have no way of knowing, leading to corrupt data that would, eventually, crash your program.
However, you can change its contents- so it's much, much more memory efficient than making a complete copy because you wanted to change a single cha...
Importing variables from another file?
...iables from file1 without flooding file2's namespace, use:
import file1
#now use file1.x1, file2.x2, ... to access those variables
To import all variables from file1 to file2's namespace( not recommended):
from file1 import *
#now use x1, x2..
From the docs:
While it is valid to use from ...
What is the best project structure for a Python application? [closed]
...
Oh, I love this trick and am using it now. I want to put the shared module in another directory, and I do not want to install module system-wide, nor do I want to ask people to modify PYTHONPATH manually. Unless people propose something better, I think this is ac...
bash: pip: command not found
...et install python3-pip
to install pip3.
Old 2013 answer (easy_install is now deprecated):
Use setuptools to install pip: sudo easy_install pip
(I know the above part of my answer is redundant with klobucar's, but I can't add comments yet), so here's an answer with a solution to sudo: easy_install:...
What is the difference between '/' and '//' when used for division?
...--> 2 Python 2.7
print (4/2) ----> 2.0 Python 3.5
Now if you want to have (in python 2.7) same output as in python 3.5, you can do the following:
Python 2.7.10
from __future__ import division
print (2/3) ----> 0.6666666666666666 #Python 2.7
print (4/2) ----> 2....
@UniqueConstraint annotation in Java
I have a Java bean. Now, I want to be sure that the field should be unique.
8 Answers
...
Why does running the Flask dev server run itself twice?
...######### Restarting @ {} ###################'.format(
datetime.utcnow())
However, if you need to set up module globals, then you should instead use the @app.before_first_request decorator on a function and have that function set up such globals. It'll be called just once after every reloa...
Cannot kill Python script with Ctrl-C
...s keep the main thread alive:
import time
while True:
time.sleep(1)
Now it will keep print 'first' and 'second' until you hit Ctrl+C.
Edit: as commenters have pointed out, the daemon threads may not get a chance to clean up things like temporary files. If you need that, then catch the Keyboa...
Comparing two NumPy arrays for equality, element-wise
...
Now use np.array_equal. From documentation:
np.array_equal([1, 2], [1, 2])
True
np.array_equal(np.array([1, 2]), np.array([1, 2]))
True
np.array_equal([1, 2], [1, 2, 3])
False
np.array_equal([1, 2], [1, 4])
False
...
How are Python's Built In Dictionaries Implemented?
Does anyone know how the built in dictionary type for python is implemented? My understanding is that it is some sort of hash table, but I haven't been able to find any sort of definitive answer.
...