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Difference between del, remove and pop on lists
...;>> a = [9, 8, 7, 6]
>>> del a[1]
>>> a
[9, 7, 6]
and pop removes the item at a specific index and returns it.
>>> a = [4, 3, 5]
>>> a.pop(1)
3
>>> a
[4, 5]
Their error modes are different too:
>>> a = [4, 5, 6]
>>> a.remove(7)
T...
How to debug a Flask app
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Running the app in development mode will show an interactive traceback and console in the browser when there is an error. To run in development mode, set the FLASK_ENV=development environment variable then use the flask run command (remember to point FLASK_APP to your app as well).
For Linux, M...
What does Ruby have that Python doesn't, and vice versa?
There is a lot of discussions of Python vs Ruby, and I all find them completely unhelpful, because they all turn around why feature X sucks in language Y, or that claim language Y doesn't have X, although in fact it does. I also know exactly why I prefer Python, but that's also subjective, and would...
How can I create an object and add attributes to it?
I want to create a dynamic object (inside another object) in Python and then add attributes to it.
16 Answers
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Finding the type of an object in C++
I have a class A and another class that inherits from it, B. I am overriding a function that accepts an object of type A as a parameter, so I have to accept an A. However, I later call functions that only B has, so I want to return false and not proceed if the object passed is not of type B.
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Changing every value in a hash in Ruby
I want to change every value in a hash so as to add '%' before and after the value so
11 Answers
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DistutilsOptionError: must supply either home or prefix/exec-prefix — not both
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Are you using OS X and Homebrew? The Homebrew python page https://github.com/Homebrew/brew/blob/master/docs/Homebrew-and-Python.md calls out a known issue with pip and a work around.
Worked for me.
You can make this "empty prefix" the def...
Extracting just Month and Year separately from Pandas Datetime column
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If you want new columns showing year and month separately you can do this:
df['year'] = pd.DatetimeIndex(df['ArrivalDate']).year
df['month'] = pd.DatetimeIndex(df['ArrivalDate']).month
or...
df['year'] = df['ArrivalDate'].dt.year
df['month'] = df['ArrivalDat...
How to use a decimal range() step value?
Is there a way to step between 0 and 1 by 0.1?
33 Answers
33
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C/C++ check if one bit is set in, i.e. int variable
... there such a way to check if bit 3 in temp is 1 or 0 without bit shifting and masking.
21 Answers
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