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Convert column classes in data.table
...hat is the idiomatic way of doing this for a subset of columns (instead of all of them)? I've defined a character vector convcols of columns. dt[,lapply(.SD,as.numeric),.SDcols=convcols] is almost instant while dt[,convcols:=lapply(.SD,as.numeric),.SDcols=convcols] almost freezes up R, so I'm guessi...
Difference between modes a, a+, w, w+, and r+ in built-in open function?
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I believe you mean the fopen call in the C standard library (which is not a system call)
– Eli Courtwright
Sep 23 '09 at 13:34
15
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How to recognize swipe in all 4 directions
...mask, but each recognizer can only handle one direction. You can send them all to the same handler if you want, and sort it out there, or send them to different handlers. Here's one implementation:
override func viewDidLoad() {
super.viewDidLoad()
let swipeRight = UISwipeGestureRecognizer(...
Could not load file or assembly 'System.Net.Http.Formatting' or one of its dependencies. The system
I have a small MVC app that I use for practice reasons, but now I am encountering an error every time I try to debug:
18 An...
Expression Versus Statement
...as one unit of execution, a thing that you did. The only reason it wasn't called a "line" was because sometimes it spanned multiple lines. An expression on its own couldn't do anything... you had to assign it to a variable.
1 + 2 / X
is an error in FORTRAN, because it doesn't do anything. You had...
Checkout subdirectories in Git?
...lace outside of the working copy) that I got used to just making lots of small single-purpose repositories.
If you insist (or really need it), though, you could make a git repository with just mytheme and myplugins directories and symlink those from within the WordPress install.
MDCore wrote:
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Making a Sass mixin with optional arguments
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A DRY'r Way of Doing It
And, generally, a neat trick to remove the quotes.
@mixin box-shadow($top, $left, $blur, $color, $inset:"") {
-webkit-box-shadow: $top $left $blur $color #{$inset};
-moz-box-shadow: $top $left $blur $color #{$inset};
box-shad...
resizes wrong; appears to have unremovable `min-width: min-content`
...scribed below is fixed as of Firefox 53 and the link to this answer has finally been removed from Bootstrap's documentation.
Also, my sincere apologies to the Mozilla contributors who had to block removing support for -moz-document partly due to this answer.
The fix
In WebKit and Firefox 53+, you...
Can git automatically switch between spaces and tabs?
...global filter.tabspace.clean 'expand --tabs=4 --initial'
OS X
First install coreutils with brew:
brew install coreutils
Now run the commands:
git config --global filter.tabspace.smudge 'gunexpand --tabs=4 --first-only'
git config --global filter.tabspace.clean 'gexpand --tabs=4 --initial'
A...
What's the best way to set a single pixel in an HTML5 canvas?
... as an exercise for the reader
creating another img or canvas filled with all the pixels you want and use drawImage() to blit just the pixel you want across. This would probably be very fast, but has the limitation that you need to pre-calculate the pixels you need.
Note that my tests do not atte...