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Append an object to a list in R in amortized constant time, O(1)?
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17 Answers
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What's the difference between eval, exec, and compile?
...ed as an expression, so it really does not return anything).
In versions 1.0 - 2.7, exec was a statement, because CPython needed to produce a different kind of code object for functions that used exec for its side effects inside the function.
In Python 3, exec is a function; its use has no effec...
Dynamically select data frame columns using $ and a character value
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185
You can't do that kind of subsetting with $. In the source code (R/src/main/subset.c) it state...
Regular expression search replace in Sublime Text 2
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Usually a back-reference is either $1 or \1 (backslash one) for the first capture group (the first match of a pattern in parentheses), and indeed Sublime supports both syntaxes. So try:
my name used to be \1
or
my name used to be $1
Also note that your or...
Is there a list of screen resolutions for all Android based phones and tablets? [closed]
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130
(out of date) Spreadsheet of device metrics.
SEE ALSO:
Device Metrics - Material Design.
Scre...
how do I work around log4net keeping changing publickeytoken
...ct which uses a couple of frameworks which is dependent on log4net version 1.2.10.0. Today I tried to include a new framework which is dependent on log4net version 1.2.11.0, I've been stuck ever since:
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Ruby max integer
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machine_bits = machine_bytes * 8
machine_max_signed = 2**(machine_bits-1) - 1
machine_max_unsigned = 2**machine_bits - 1
If you are looking for the size of Fixnum objects (integers small enough to store in a single machine word), you can call 0.size to get the number of bytes. I would guess ...
What is the easiest way to push an element to the beginning of the array?
...f self, moving other elements upwards.
And in use:
irb>> a = [ 0, 1, 2]
=> [0, 1, 2]
irb>> a.unshift('x')
=> ["x", 0, 1, 2]
irb>> a.inspect
=> "["x", 0, 1, 2]"
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Try-finally block prevents StackOverflowError
...evel into the finally block take twice as long an the stack depth could be
10,000 or more. If you can make 10,000,000 calls per second, this will take 10^3003 seconds or longer than the age of the universe.
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How to validate an Email in PHP?
... a small amount of differences, reading the Manual should suffice.
Update 1: As pointed out by @binaryLV:
PHP 5.3.3 and 5.2.14 had a bug related to
FILTER_VALIDATE_EMAIL, which resulted in segfault when validating
large values. Simple and safe workaround for this is using strlen()
before...