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Aren't Python strings immutable? Then why does a + “ ” + b work?
My understanding was that Python strings are immutable.
22 Answers
22
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Sort a list of tuples by 2nd item (integer value) [duplicate]
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This still works well with Python 3.7.
– jftuga
Oct 30 '18 at 20:44
3
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Plotting a list of (x, y) coordinates in python matplotlib
...ve a list of pairs (a, b) that I would like to plot with matplotlib in python as actual x-y coordinates. Currently, it is making two plots, where the index of the list gives the x-coordinate, and the first plot's y values are the a s in the pairs and the second plot's y values are the b s in t...
How to generate keyboard events in Python?
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For both python3 and python2 you can use pyautogui (pip install pyautogui)
from pyautogui import press, typewrite, hotkey
press('a')
typewrite('quick brown fox')
hotkey('ctrl', 'w')
It's also crossplatform with Windows, OSX, and U...
How to get year, month, day, hours, minutes, seconds and milliseconds of the current moment in Java?
... midnight in Paris France is a new day while still “yesterday” in Montréal Québec.
If no time zone is specified, the JVM implicitly applies its current default time zone. That default may change at any moment during runtime(!), so your results may vary. Better to specify your desired/expected...
ImportError: Cannot import name X
.... This is extremely important in C++, and even if it's not the #1 thing in Python, it's still a really good idea to follow this rule. Never have two classes which know each other, ever. If you need help with creating the structure for your classes, post rest of the code too. How exactly (in terms of...
Create numpy matrix filled with NaNs
...atives a[:] = numpy.nan here and a.fill(numpy.nan) as posted by Blaenk:
$ python -mtimeit "import numpy as np; a = np.empty((100,100));" "a.fill(np.nan)"
10000 loops, best of 3: 54.3 usec per loop
$ python -mtimeit "import numpy as np; a = np.empty((100,100));" "a[:] = np.nan"
10000 loops, best of...
File I/O in Every Programming Language [closed]
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Python 3
with open('fileio.txt', 'w') as f:
f.write('hello')
with open('fileio.txt', 'a') as f:
f.write('\nworld')
with open('fileio.txt') as f:
s = f.readlines()[1]
print(s)
Clarifications
readlines() returns a...
Python string.join(list) on object array rather than string array
In Python, I can do:
4 Answers
4
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Python - json without whitespaces
...hile indent=None (default) does not in 2.7. All is clearly stated at: docs.python.org/3/library/json.html#json.dump
– Ciro Santilli 郝海东冠状病六四事件法轮功
Jul 28 '16 at 14:01
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