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Can anyone explain python's relative imports?
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how to permit an array with strong parameters
I have a functioning Rails 3 app that uses has_many :through associations which is not, as I remake it as a Rails 4 app, letting me save ids from the associated model in the Rails 4 version.
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How to properly check if std::function is empty in C++11?
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Rails migrations: Undo default setting for a column
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387
Rails 5+
def change
change_column_default( :table_name, :column_name, from: nil, to: fals...
How do I install Python packages on Windows?
...environment so that you can use pip anywhere. It's somewhere like C:\Python33\Scripts.
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How are multi-dimensional arrays formatted in memory?
...eter, bad things are going to happen. Here's a quick example:
int array1[3][2] = {{0, 1}, {2, 3}, {4, 5}};
In memory looks like this:
0 1 2 3 4 5
exactly the same as:
int array2[6] = { 0, 1, 2, 3, 4, 5 };
But if you try to pass array1 to this function:
void function1(int **a);
you'll ge...
What does @hide mean in the Android source code?
For the Activity source code , line 3898 (close to the bottom):
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How can I safely create a nested directory?
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On Python ≥ 3.5, use pathlib.Path.mkdir:
from pathlib import Path
Path("/my/directory").mkdir(parents=True, exist_ok=True)
For older versions of Python, I see two answers with good qualities, each with a small flaw, so I will give my ...
What is the difference between NaN and None?
...= pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype
Out[13]: dtype('O')
In [14]: s_good.dtype
Out[14]: dtype('float64')
Jeff comments (below) on this:
np.nan allows for vectorized operations; its a float value, while None, by definition, forces object ty...
Python regex find all overlapping matches?
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