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Split string every nth character?
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574
>>> line = '1234567890'
>>> n = 2
>>> [line[i:i+n] for i in range(0, ...
Why does changing the sum order returns a different result?
...of binary floating point, we were using a decimal floating point type with 4 significant digits, where each addition is performed at "infinite" precision and then rounded to the nearest representable number. Here are two sums:
1/3 + 2/3 + 2/3 = (0.3333 + 0.6667) + 0.6667
= 1.000 + 0...
How are echo and print different in PHP? [duplicate]
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From:
http://web.archive.org/web/20090221144611/http://faqts.com/knowledge_base/view.phtml/aid/1/fid/40
Speed. There is a difference between the two, but speed-wise it
should be irrelevant which one you use. echo is marginally faster
since it doesn't set a retur...
Can an interface extend multiple interfaces in Java?
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174
Yes, you can do it. An interface can extend multiple interfaces, as shown here:
interface Maini...
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
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edited Apr 16 '18 at 21:54
answered Feb 21 '14 at 20:54
Mi...
Android 4.3 menu item showAsAction=“always” ignored
I'm using the new v7 appcompat library available starting from Android 4.3 (API level 18).
12 Answers
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Transaction marked as rollback only: How do I find the cause
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Ean VEan V
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Remove all occurrences of a value from a list?
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524
Functional approach:
Python 3.x
>>> x = [1,2,3,2,2,2,3,4]
>>> list(filter((2...
count the frequency that a value occurs in a dataframe column
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446
Use groupby and count:
In [37]:
df = pd.DataFrame({'a':list('abssbab')})
df.groupby('a').coun...