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Open terminal here in Mac OS finder [closed]
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As of Mac OS X Lion 10.7, Terminal includes exactly this functionality as a Service. As with most Services, these are disabled by default, so you'll need to enable this to make it appear in the Services menu.
System Preferences > K...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 6
#> 2 2 6
#> 3 3 0
One additional note to go with @Moody_Mudskipper's answer: Using .drop=FALSE can give potentially...
Should I use px or rem value units in my CSS? [closed]
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TL;DR: use px.
The Facts
First, it's extremely important to know that per spec, the CSS px unit does not equal one physical display pixel. This has always been true – even in the 1996 CSS 1 spec.
CSS defines the reference pixel, w...
Validating IPv4 addresses with regexp
I've been trying to get an efficient regex for IPv4 validation, but without much luck. It seemed at one point I had had it with (25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?(\.|$)){4} , but it produces some strange results:
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Send POST data using XMLHttpRequest
I'd like to send some data using an XMLHttpRequest in JavaScript.
13 Answers
13
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Will Dispose() be called in a using statement with a null object?
...using statement on a (potentially) null object?
Consider the following example:
5 Answers
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CSS force image resize and keep aspect ratio
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img {
display: block;
max-width:230px;
max-height:95px;
width: auto;
height: auto;
}
<p>This image is originally 400x400 pixels, but should get resized by the CSS:</p>
<img width="400" height="400" src="http://i.stack.imgu...
Batch files - number of command line arguments
...ing a bit gives you the following result from wikibooks:
set argC=0
for %%x in (%*) do Set /A argC+=1
echo %argC%
Seems like cmd.exe has evolved a bit from the old DOS days :)
share
|
improve th...
Does Eclipse have line-wrap
I'm editing an XML file with the Eclipse IDE and need to input paragraphs of text. It doesn't seem that eclipse has a line-wrap feature though. Anyone knows if it does or if there's a plugin for that?
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Why '&&' and not '&'?
...eaning that the evaluation is canceled as soon as the result is clear.
Example:
if(CanExecute() && CanSave())
{
}
If CanExecute returns false, the complete expression will be false, regardless of the return value of CanSave. Because of this, CanSave is not executed.
This is very handy...