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Why is rbindlist “better” than rbind?
...
rbindlist is an optimized version of do.call(rbind, list(...)), which is known for being slow when using rbind.data.frame
Where does it really excel
Some questions that show where rbindlist shines are
Fast vectorized merge of list of data.frames by row
Trouble converting long list of data.fra...
How to use Git?
... just edit the Answer (added an alternate to a dead link). If not, let me know. (I figured it's easier to just ask YOU than to find the rule on this)
– Clay Nichols
Aug 14 '16 at 16:22
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What is the JavaScript convention for no operation?
...s shown here:
setTimeout(function() {
console.log('Start: ', Date.now());
Function.prototype();
console.log('End : ', Date.now());
}, 1000);
Although this is a "true noop" since most browsers seem to do nothing to execute the noop defined this way (and hence save CPU cyc...
Finding the number of days between two dates
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$now = time(); // or your date as well
$your_date = strtotime("2010-01-31");
$datediff = $now - $your_date;
echo round($datediff / (60 * 60 * 24));
...
How to install and run phpize
...phpize it. I installed php5-dev by sudo apt-get install php5-dev . But now when I run phpize I get the following error :
...
Virtual Serial Port for Linux
...en another terminal and write (Terminal 2):
echo "Test" > /dev/pts/3
Now back to Terminal 1 and you'll see the string "Test".
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Perl build, unit testing, code coverage: A complete working example
...rg eq "true") {
return "true";
}
else {
return "unknown";
}
return "Unreachable code: cannot be covered";
}
1;
In the "t" directory, create a text file named "HelloPerlBuildWorld.t". This file is your unit test script that will attempt to fully test your Perl modu...
How to ISO 8601 format a Date with Timezone Offset in JavaScript?
...the format required by the spec that you referenced.
This format is also known as ISO8601, or more precisely as RFC3339.
In this format, UTC is represented with a Z while all other formats are represented by an offset from UTC. The meaning is the same as JavaScript's, but the order of subtraction...
How do I run multiple instances of Android Studio
...ings -> Project Opening.
Check [x] "Confirm window to open project in".
Now open the other (2nd) project with File -> Open... etc.
You will now be asked if you want to open a new window or replace what you already have. Select New Window.
Screenshots:
Older versions:
Go to Setting...
EC2 Can't resize volume after increasing size
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This answer is now deprecated now that AWS supports online resizing for EBS volumes.
– Dale Anderson
Jul 6 '17 at 17:49
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