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How do I sort an observable collection?
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Sorting an observable and returning the same object sorted can be done using an extension method. For larger collections watch out for the number of collection changed notifications.
I have updated my code to improve performance (thanks to nawfal)...
How to use shared memory with Linux in C
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There are two approaches: shmget and mmap. I'll talk about mmap, since it's more modern and flexible, but you can take a look at man shmget (or this tutorial) if you'd rather use the old-style tools.
The mmap() function can be used to allocate memory buffer...
List comprehension in Ruby
... % 2 == 0 ? x * 3 : nil}.compact
Slightly cleaner, at least to my taste, and according to a quick benchmark test about 15% faster than your version...
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Select multiple columns in data.table by their numeric indices
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No problem. Compare also dt[,"a"] and dt[,"a", with=FALSE] to see what a helpful option it really is.
– Josh O'Brien
Nov 14 '12 at 17:41
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How to get Chrome to allow mixed content?
... list is "Insecure content", change this to Allow
Go back to the site and Refresh the page
Older Chrome Versions:
timmmy_42 answers this on: https://productforums.google.com/forum/#!topic/chrome/OrwppKWbKnc
In the address bar at the right end should be a 'shield' icon, you can
click ...
INSTALL_FAILED_UPDATE_INCOMPATIBLE when I try to install compiled .apk on device
I've compiled Trebuchet launcher from CyanogenMod 9, and trying to install it with adb:
29 Answers
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Creating a UIImage from a UIColor to use as a background image for UIButton [duplicate]
...egory around UIButton to be able to set the background color of the button and set the state. You might find this useful.
@implementation UIButton (ButtonMagic)
- (void)setBackgroundColor:(UIColor *)backgroundColor forState:(UIControlState)state {
[self setBackgroundImage:[UIButton imageFromC...
Viewing contents of a .jar file
... @salvob You don't need the hyphen as it takes after tar with the options mandatory.
– Tom Hawtin - tackline
Jan 12 '17 at 16:51
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Printing without newline (print 'a',) prints a space, how to remove?
...aaaaaaaaaaaaaaaaaaa
If you want to do this in general, build up a string and then print it once. This will consume a bit of memory for the string, but only make a single call to print. Note that string concatenation using += is now linear in the size of the string you're concatenating so this will...
List comprehension: Returning two (or more) items for each item
...would incidentally eliminate khachik's complaint. (Though in a sense, mine and his are essentially the same in terms of process. We simply define the inner generator differently.)
– JAB
Aug 8 '12 at 16:40
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