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Summarizing multiple columns with dplyr? [duplicate]
...;int> <dbl> <dbl> <dbl> <dbl>
#> 1 1 3.08 2.98 2.98 2.91
#> 2 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
If you want to summarize only certain columns, use summarise_at or summarise_if functions.
Alternatively, the purrrlyr package p...
How to tell if a file is git tracked (by shell exit code)?
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Regexp Java for password validation
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318
Try this:
^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%^&+=])(?=\S+$).{8,}$
Explanation:
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How to select the last record of a table in SQL?
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answered Mar 4 '11 at 8:48
Adriaan StanderAdriaan Stander
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“please check gdb is codesigned - see taskgated(8)” - How to get gdb installed with homebrew code si
I'm under osx 10.8.4 and have installed gdb 7.5.1 with homebrew (motivation get a new gdb with new features such as --with-python etc... )
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Which is faster: while(1) or while(2)?
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Both loops are infinite, but we can see which one takes more instructions/resources per iterati...
What is the difference between square brackets and parentheses in a regex?
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These regexes are equivalent (for matching purposes):
/^(7|8|9)\d{9}$/
/^[789]\d{9}$/
/^[7-9]\d{9}$/
The explanation:
(a|b|c) is a regex "OR" and means "a or b or c", although the presence of brackets, necessary for the OR, also captures the digit. To be strictly equivalent, you...
Check if string ends with one of the strings from a list
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What is the difference between BIT and TINYINT in MySQL?
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A TINYINT is an 8-bit integer value, a BIT field can store between 1 bit, BIT(1), and 64 bits, BIT(64). For a boolean values, BIT(1) is pretty common.
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