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how do I initialize a float to its max/min value?
...s). It just seems to make sense to me to initialize it rather than preform extra checks to ensure the first element is not zero.
– Faken
Apr 21 '10 at 16:31
...
PHP abstract properties
...get_class($this) . ' must have a $tablename');
}
}
To enforce this for all derived classes of Foo_Abstract you would have to make Foo_Abstract's constructor final, preventing overriding.
You could declare an abstract getter instead:
abstract class Foo_Abstract {
abstract public function get_...
How to make a phone call using intent in Android?
...
More elegant option:
String phone = "+34666777888";
Intent intent = new Intent(Intent.ACTION_DIAL, Uri.fromParts("tel", phone, null));
startActivity(intent);
share
...
How can I get the latest JRE / JDK as a zip file rather than EXE or MSI installer? [closed]
... of JDK from Oracle (for example jdk-7u7-windows-x64.exe)
Download and install 7-Zip (or download 7-Zip portable version if you are not administrator)
With 7-Zip extract all the files from jdk-XuXX-windows-x64.exe into the directory C:\JDK
Execute the following commands in cmd.exe:
cd C:\JDK\.rsrc...
How do I handle too long index names in a Ruby on Rails ActiveRecord migration?
...
According to APIdock the name has to be a string, not a symbol
– Jaco Pretorius
Dec 31 '13 at 14:38
7
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How do you round a floating point number in Perl?
.... For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implements
ceil(), floor(), and a number of other mathematical and trigonometric
func...
Change UICollectionViewCell size on different device orientations
...ls with animation (you can just pass nil to both block params if you've no extra adjustments to perform).
2) Instead of hardcoding the item sizes in -collectionView:layout:sizeForItemAtIndexPath, just divide the height or width of the collectionView's bounds by the number of cells you want to fit o...
Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...
What are the advantages of NumPy over regular Python lists?
... Python objects, at least 4 bytes per pointer plus 16 bytes for even the smallest Python object (4 for type pointer, 4 for reference count, 4 for value -- and the memory allocators rounds up to 16). A NumPy array is an array of uniform values -- single-precision numbers takes 4 bytes each, double-pr...
What is the difference between Θ(n) and O(n)?
...e of the algorithm as n gets larger is at most proportional to g(n).
Normally, even when people talk about O(g(n)) they actually mean Θ(g(n)) but technically, there is a difference.
More technically:
O(n) represents upper bound. Θ(n) means tight bound.
Ω(n) represents lower bound.
...