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Pass a data.frame column name to a function
...(x[,column])
}
fun1(df, "B", max)
Alternatively, using [[ also works for selecting a single column at a time:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[[column]])
}
fun1(df, "B")
...
Best way to give a variable a default value (simulate Perl ||, ||= )
...
return true;
} else {
return false;
}
}
function select_defined(){
$l = func_num_args();
$a = func_get_args();
for ($i=0; $i<$l; $i++){
if ($a[$i]) return $a[$i];
}
}
Examples:
// $foo ||= $bar;
set_unless_defined($foo, $bar);
//$foo = $baz ||...
How to get the list of all installed color schemes in Vim?
...a list of all installed color schemes in Vim? That would make very easy to select one without looking at the .vim directory.
...
Word wrap for a label in Windows Forms
...
Select the label you're dynamically adding text to. Look at the properties for the label and turn off AutoSize. You will now be able to drag/set the area for the label and it will automatically auto-wrap to stay within those...
Failed to load c++ bson extension
...vailable when you installed your mongodb library. I suggest you do
xcode-select --install (on a mac)
or sudo apt-get install gcc make build-essential (on ubuntu)
and run
rm -rf node_modules
npm cache clean
npm install
OR just npm update based on @tobias comment (after installing build-essenti...
How to create a video from images with FFmpeg?
...
-pattern_type glob
This great option makes it easier to select the images in many cases.
Slideshow video with one image per second
ffmpeg -framerate 1 -pattern_type glob -i '*.png' \
-c:v libx264 -r 30 -pix_fmt yuv420p out.mp4
Add some music to it, cutoff when the presumably...
Fancybox doesn't work with jQuery v1.9.0 [ f.browser is undefined / Cannot read property 'msie' ]
...' + ($.browser.msie ? 'allowtransparency="true""' : '') + ' scrolling="' + selectedOpts.scrolling + '" src="' + currentOpts.href + '"></iframe>').appendTo(content);
+ $('<iframe id="fancybox-frame" name="fancybox-frame' + new Date().getTime() + '" frameborder="0" hspace="0"...
Java project in Eclipse: The type java.lang.Object cannot be resolved. It is indirectly referenced f
...teps could help:
Right-click on project » Properties » Java Build Path
Select Libraries tab
Find the JRE System Library and remove it
Click Add Library... button at right side » Add the JRE System Library (Workspace default JRE)
...
How to trigger a click on a link using jQuery
...
@Kit .find() is a faster selector than what you are proposing, do a benchmark if you disagree but your proposal slows it down. positively :-)
– Ady Ngom
Apr 27 '11 at 22:22
...
Custom fonts in iOS 7
... font you imported to your app is being packed into app itself. Do that by selecting your Target, then Build Phases, then Copy Bundle Resources. If you don't see your font in there, drag it from Supporting Files.
Finally, you would like to list all your fonts when the app starts just to see useabl...