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Is there a way to avoid null check before the for-each loop iteration starts? [duplicate]
Every time I have to iterate over a collection I end up checking for null, just before the iteration of the for-each loop starts. Like this:
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Why there is no ConcurrentHashSet against ConcurrentHashMap
...map (or map class).
Prior to Java 8, you produce a concurrent hash set backed by a concurrent hash map, by using Collections.newSetFromMap(map)
In Java 8 (pointed out by @Matt), you can get a concurrent hash set view via ConcurrentHashMap.newKeySet(). This is a bit simpler than the old newSetFromM...
In Matlab, when is it optimal to use bsxfun?
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There are three reasons I use bsxfun (documentation, blog link)
bsxfun is faster than repmat (see below)
bsxfun requires less typing
Using bsxfun, like using accumarray, makes me feel good about my understanding of Matlab.
bsxfun will replicate the input arrays along their "singlet...
Simple regular expression for a decimal with a precision of 2
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Valid regex tokens vary by implementation. A generic form is:
[0-9]+(\.[0-9][0-9]?)?
More compact:
\d+(\.\d{1,2})?
Both assume that both have at least one digit before and one after the decimal place.
To require that the whole strin...
How to add a right button to a UINavigationController?
...d it still might be quite a while before it displays, no point in doing work early and tying up memory.
- (void)viewDidLoad {
[super viewDidLoad];
UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithTitle:@"Show" style:UIBarButtonItemStylePlain target:self action:@selector(refres...
Is there a better way to iterate over two lists, getting one element from each list for each iterati
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Roberto BonvalletRoberto Bonvallet
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How do I remove  from the beginning of a file?
I have a CSS file that looks fine when I open it using gedit , but when it's read by PHP (to merge all the CSS files into one), this CSS has the following characters prepended to it: 
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Equation for testing if a point is inside a circle
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jasonjason
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Saving image from PHP URL
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Andrew
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answered Apr 7 '09 at 7:15
vartecvartec
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Calling dynamic function with dynamic number of parameters [duplicate]
I’m looking for a trick about this. I know how to call a dynamic, arbitrary function in JavaScript, passing specific parameters, something like this:
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