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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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Remove the last line from a file in Bash
...$ d' foo.txt
The -i option does not exist in GNU sed versions older than 3.95, so you have to use it as a filter with a temporary file:
cp foo.txt foo.txt.tmp
sed '$ d' foo.txt.tmp > foo.txt
rm -f foo.txt.tmp
Of course, in that case you could also use head -n -1 instead of sed.
MacOS:
On M...
How can I safely create a nested directory?
...
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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How to map with index in Ruby?
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answered Jan 15 '11 at 1:37
sepp2ksepp2k
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How do I detach objects in Entity Framework Code First?
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saluce
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answered Apr 8 '11 at 20:00
Ladislav MrnkaLadislav...
finding the type of an element using jQuery
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