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How do I convert a pandas Series or index to a Numpy array? [duplicate]
Do you know how to get the index or column of a DataFrame as a NumPy array or python list?
8 Answers
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What do all of Scala's symbolic operators mean?
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I divide the operators, for the purpose of teaching, into four categories:
Keywords/reserved symbols
Automatically imported methods
Common methods
Syntactic sugars/composition
It is fortunate, then, that most categories are represented in t...
Difference between “and” and && in Ruby?
What is the difference between the && and and operators in Ruby?
7 Answers
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Difference between return and exit in Bash functions
...that of the last command executed. A trap on EXIT is executed before the shell terminates.
EDIT:
As per your edit of the question, regarding exit codes, return has nothing to do with exit codes. Exit codes are intended for applications/scripts, not functions. So in this regard, the only...
Regex to match a digit two or four times
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There's no specific syntax for that, but there are lots of ways to do it:
(?:\d{4}|\d{2}) <-- alternation: four digits or two
\d{2}(?:\d{2})? <-- two digits, and optionally two more
(?:\d{2}){1,2} <-- two digits, times one or two
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Python Infinity - Any caveats?
...ic involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440...
How can I replace a newline (\n) using sed?
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Append the current and next line to the pattern space via N.
If we are before the last line, branch to the created label $!ba ($! means not to do it on the last line as there should be one final newline).
Finally the substitution replaces every newline with a space on the pattern space (which is th...
Convert JavaScript string in dot notation into an object reference
...'m flattered that this answer has gotten many upvotes, I am also somewhat horrified. If one needs to convert dot-notation strings like "x.a.b.c" into references, it could (maybe) be a sign that there is something very wrong going on (unless maybe you're performing some strange deserialization).
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Big-O summary for Java Collections Framework implementations? [closed]
...O notation, it is probably not safe to assume that they will know what the order of the various operations on various collection implementations is.
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How to chain scope queries with OR instead of AND?
I'm using Rails3, ActiveRecord
19 Answers
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