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Add up a column of numbers at the Unix shell
... . . .| x=$(echo <(cat)); echo $((0+${x// /+}+0)) if you want all bash all the time:
– qneill
Apr 3 '15 at 23:31
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How does the MapReduce sort algorithm work?
... 1 sampled keys that define the key range for each reduce. In particular, all keys such that sample[i − 1] <= key < sample[i] are sent to reduce i. This guarantees that the output of reduce i are all less than the output of reduce i+1."
So their trick is in the way they determine the keys ...
If isset $_POST
....
empty space is considered as set. You need to use empty() for checking all null options.
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Numpy `logical_or` for more than two arguments
... no, as the docs explicitly say, the only parameters are x1, x2, and optionally out:
numpy.logical_or(x1, x2[, out]) = <ufunc 'logical_or'>
You can of course chain together multiple logical_or calls like this:
>>> x = np.array([True, True, False, False])
>>> y = np.a...
What is the default text size on Android?
...ues are defined within the following TextAppearances:
- TextAppearance.Small
- TextAppearance.Medium
- TextAppearance.Large
More information about Typography can be found in the design guidelines
Related to your question:
If you don't set a custom textSize or textAppearance, TextAppearance.S...
How do I check if a string contains another string in Swift?
... and containsIgnoringCase for String
extension String {
func contains(_ find: String) -> Bool{
return self.range(of: find) != nil
}
func containsIgnoringCase(_ find: String) -> Bool{
return self.range(of: find, options: .caseInsensitive) != nil
}
}
Older Swift vers...
What's the use of ob_start() in php?
...Think of ob_start() as saying "Start remembering everything that would normally be outputted, but don't quite do anything with it yet."
For example:
ob_start();
echo("Hello there!"); //would normally get printed to the screen/output to browser
$output = ob_get_contents();
ob_end_clean();
There a...
How to combine two or more querysets in a Django view?
...sets into a list is the simplest approach. If the database will be hit for all querysets anyway (e.g. because the result needs to be sorted), this won't add further cost.
from itertools import chain
result_list = list(chain(page_list, article_list, post_list))
Using itertools.chain is faster than...
How do you build a Singleton in Dart?
... There's the weird syntax Singleton._internal(); that looks like a method call when it's really a constructor definition. There's the _internal name. And there's the nifty language design point that Dart lets you start out (dart out?) using an ordinary constructor and then, if needed, change it to a...
How can the Euclidean distance be calculated with NumPy?
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There's a function for that in SciPy. It's called Euclidean.
Example:
from scipy.spatial import distance
a = (1, 2, 3)
b = (4, 5, 6)
dst = distance.euclidean(a, b)
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