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What is the most robust way to force a UIView to redraw?
... building my view hierarchy. the subclass in question gets passed the data and it's drawRect method now has everything it needs to render.
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Should I be using object literals or constructor functions?
...If you want to add behaviour to your object, you can go with a constructor and add methods to the object during construction or give your class a prototype.
function MyData(foo, bar) {
this.foo = foo;
this.bar = bar;
this.verify = function () {
return this.foo === this.bar;
...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...
Bottom Line
Use either COUNT(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those ...
In Bash, how can I check if a string begins with some value?
... So is there a functional difference between [[ $a == z* ]] and [[ $a == "z*" ]]? In other words: do they work differently? And what specifically do you mean when you say "$a is equal to z*"?
– Niels Bom
Jun 16 '15 at 10:37
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Geometric Mean: is there a built-in?
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Here is a vectorized, zero- and NA-tolerant function for calculating geometric mean in R. The verbose mean calculation involving length(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log...
Why is my program slow when looping over exactly 8192 elements?
...rom the program in question. The matrix img[][] has the size SIZE×SIZE, and is initialized at:
2 Answers
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Creating a config file in PHP
...urn array(
'host' => 'localhost',
'username' => 'root',
);
And then:
$configs = include('config.php');
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What does FETCH_HEAD in Git mean?
... @Jefromi: sorry, i think you are wrong: as far as i understand, git fetch updates (merges) all object data from the remote storage, not just a brunch. So i do not understand from your answer how git decides to the tip of which branch to point FETCH_HEAD. I also cannot find FETCH_HE...
Differences between Intent and PendingIntent
I read through some articles and both seem to do the same thing and I was wondering what is the difference between starting the service like that:
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In JavaScript, why is “0” equal to false, but when tested by 'if' it is not false by itself?
...you explicitly do "0" == false, both sides are being converted to numbers, and then the comparison is performed.
When you do: if ("0") console.log("ha"), the string value is being tested. Any non-empty string is true, while an empty string is false.
Equal (==)
If the two operands are not o...