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Store boolean value in SQLite
...an storage class. Instead, Boolean values are stored as integers 0 (false) and 1 (true).
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How to use R's ellipsis feature when writing your own function?
...nts. For example, the function data.frame takes any number of arguments, and each argument becomes the data for a column in the resulting data table. Example usage:
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Drop rows with all zeros in pandas data frame
I can use pandas dropna() functionality to remove rows with some or all columns set as NA 's. Is there an equivalent function for dropping rows with all columns having value 0?
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What is the difference between an expression and a statement in Python?
In Python, what is the difference between expressions and statements?
14 Answers
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How do SQL EXISTS statements work?
I'm trying to learn SQL and am having a hard time understanding EXISTS statements. I came across this quote about "exists" and don't understand something:
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Listing each branch and its last revision's date in Git
I need to delete old and unmaintained branches from our remote repository. I'm trying to find a way with which to list the remote branches by their last modified date, and I can't.
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Regular expression that matches valid IPv6 addresses
...ular expressions, so I wrote one that works with POSIX regular expressions and PERL regular expressions.
It should match:
IPv6 addresses
zero compressed IPv6 addresses (section 2.2 of rfc5952)
link-local IPv6 addresses with zone index (section 11 of rfc4007)
IPv4-Embedded IPv6 Address (section 2 ...
What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...mbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.org/software/coreutils/manual/html_node/sort-invocatio...
Sorting multiple keys with Unix sort
...s that need to be sorted by 1-n keys. Some of these keys might be numeric and some of them might not be. This is a fixed-width columnar file so there are no delimiters.
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Why does typeof NaN return 'number'?
...eration
which return NaN:
Operations with a NaN as at least one operand
Indeterminate forms
The divisions 0/0, ∞/∞, ∞/−∞, −∞/∞, and −∞/−∞
The multiplications 0×∞ and 0×−∞
The power 1^∞
The additions ∞ + (−∞), (−∞) + ∞ and e...