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Merge/flatten an array of arrays
...boGumbo
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10
...
Pandas: drop a level from a multi-level column index?
...tuples([("a", "b"), ("a", "c")])
>>> df = pd.DataFrame([[1,2], [3,4]], columns=cols)
>>> df
a
b c
0 1 2
1 3 4
[2 rows x 2 columns]
>>> df.columns = df.columns.droplevel()
>>> df
b c
0 1 2
1 3 4
[2 rows x 2 columns]
...
Bitwise operation and usage
...0 1 1 | 1 1 1 | 1 0
One example is if you only want the lower 4 bits of an integer, you AND it with 15 (binary 1111) so:
201: 1100 1001
AND 15: 0000 1111
------------------
IS 9 0000 1001
The zero bits in 15 in that case effectively act as a filter, forcing the bits in the r...
Is there a Python function to determine which quarter of the year a date is in?
...eted), were buggy -- not doing the -1 before the division, and dividing by 4 instead of 3. Since .month goes 1 to 12, it's easy to check for yourself what formula is right:
for m in range(1, 13):
print m//4 + 1,
print
gives 1 1 1 2 2 2 2 3 3 3 3 4 -- two four-month quarters and a single-month ...
Why do 64-bit DLLs go to System32 and 32-bit DLLs to SysWoW64 on 64-bit Windows?
...s hard-coded for that path, that it wasn't feasible to remove it.
SysWoW64 wasn't intended for the dlls of 64-bit systems, it's actually something like "Windows on Windows64", meaning the bits you need to run 32bit apps on a 64bit windows.
This article explains a bit:
"Windows x64 has a directo...
Converting String to “Character” array in Java
... |
edited Jan 29 '14 at 22:45
David Newcomb
9,71833 gold badges3838 silver badges5353 bronze badges
...
Python: Ignore 'Incorrect padding' error when base64 decoding
I have some data that is base64 encoded that I want to convert back to binary even if there is a padding error in it. If I use
...
Difference between android-support-v7-appcompat and android-support-v4
I wanted to know the difference between android-support-v4.jar
and android-support-v7-appcompat.jar . If I want to add appcompat Action Bar in my application do I need to add both android-support-v7-appcompat.jar and android-support-v4.jar or only android-support-v7-appcompat.jar .
...
npm windows install globally results in npm ERR! extraneous
...
answered Mar 25 '14 at 4:30
Kyle Robinson YoungKyle Robinson Young
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...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...
1646
These two collations are both for the UTF-8 character encoding. The differences are in how tex...