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Paging UICollectionView by cells, not screen
...nformance and set a value for pageWidth:
func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
let pageWidth = // The width your page should have (plus a possible margin)
let proportionalOffset = collectionView.contentOffset.x / pageWidth
indexOfCellBeforeDragging = Int(round(p...
Standardize data columns in R
...
z = runif(10, 10, 20))
dat
dat2 <- dat %>% mutate_at(c("y", "z"), ~(scale(.) %>% as.vector))
dat2
which gives me this:
> dat
x y z
1 29.75859 3.633225 14.56091
2 30.05549 3.605387 12.65187
3 30.21689 3.318092 13.04672
4 29.53086 3.079992...
Genymotion, “Unable to load VirtualBox engine.” on Mavericks. VBox is setup correctly
...s by installing VirtualBox 4.3.28 (https://www.virtualbox.org/wiki/Download_Old_Builds_4_3). The new 5.0.0 and 4.3.30 versions didn't work for me with Genymotion 2.5. None of the above solutions worked :(
It's also worth noting that at the time of writing, Genymotion's FAQ states the following:
...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
... (with corresponding RX flashes on the board) right before the avrdude: ser_recv(): programmer is not responding error.
The trick is to hit the reset button on the board immediately before these three packets are sent. Then the program will be uploaded successfully.
...
Absolute vs relative URLs
...
See this: http://en.wikipedia.org/wiki/URI_scheme#Generic_syntax
foo://username:password@example.com:8042/over/there/index.dtb;type=animal?name=ferret#nose
\ / \________________/\_________/ \__/ \___/ \_/ \_________/ \_________/ \__/
| | ...
Always pass weak reference of self into block in ARC?
...olve by making an explicitly weak reference to self for the block to use:
__weak MyObject *weakSelf = self;
[self setMyBlock:^(id obj, NSUInteger idx, BOOL *stop) {
[weakSelf doSomethingWithObj:obj];
}];
But this should not be the default pattern you follow when dealing with blocks that ca...
Regular expressions in an Objective-C Cocoa application
...ar expressions for substring searches, e.g. [myString rangeOfString:@"regex_here" options:NSRegularExpressionSearch]
– Nestor
Apr 28 '11 at 15:23
1
...
Concurrent HashSet in .NET Framework?
...byte (1 byte in memory).
private ConcurrentDictionary<string, byte> _data;
This is the recommended option because the type is thread-safe and provide you the same advantages than a HashSet<T> except key and value are different objects.
Source: Social MSDN
ConcurrentBag
If you don't...
is node.js' console.log asynchronous?
...ed, I've added some comments to explain things:
.... code here...
process.__defineGetter__('stdout', function() {
if (stdout) return stdout; // only initialize it once
/// many requires here ...
if (binding.isatty(fd)) { // a terminal?...
Drawing a connecting line between two elements [closed]
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