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Return type of '?:' (ternary conditional operator)
...alue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues and prvalues.)
In very broad and simple terms, an lvalue refers to an object in memory and an rvalue is just a value that may not necessarily be attached to an object in memory.
An...
How do I check if a string contains another string in Swift?
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You can do exactly the same call with Swift:
Swift 4 & Swift 5
In Swift 4 String is a collection of Character values, it wasn't like this in Swift 2 and 3, so you can use this more concise code1:
let string = "hello Swift"
if string.contains("Swift") {
p...
Is there a way to detect if an image is blurry?
I was wondering if there is a way to determine if an image is blurry or not by analyzing the image data.
12 Answers
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How to find out the number of CPUs using python
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If you have python with a version >= 2.6 you can simply use
import multiprocessing
multiprocessing.cpu_count()
http://docs.python.org/library/multiprocessing.html#multiprocessing.cpu_count
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Multiple Updates in MySQL
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If there is no duplicates then i dont want that row to be inserted. what should id do? because i am fetching information from another site which maintains tables with id's. I am inserting values with respect to that id. if th...
Is there a better way of writing v = (v == 0 ? 1 : 0); [closed]
I want to toggle a variable between 0 and 1. If it's 0 I want to set it to 1, else if it's 1 I want to set it to 0.
31 Answ...
Limiting number of displayed results when using ngRepeat
...on step 5 and I thought as an experiment I’d try to allow users to specify how many they’d like to be shown. The view looks like this:
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How to split a string in shell and get the last field
...). How do I do that using Bash? I tried cut , but I don't know how to specify the last field with -f .
17 Answers
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Implementing slicing in __getitem__
...y) and my __getitem__ looks like this:
def __getitem__( self, key ) :
if isinstance( key, slice ) :
#Get the start, stop, and step from the slice
return [self[ii] for ii in xrange(*key.indices(len(self)))]
elif isinstance( key, int ) :
if key < 0 : #Handle negativ...
Efficient way to remove keys with empty strings from a dict
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Python 2.X
dict((k, v) for k, v in metadata.iteritems() if v)
Python 2.7 - 3.X
{k: v for k, v in metadata.items() if v is not None}
Note that all of your keys have values. It's just that some of those values are the empty string. There's no such thing as a key in a dict w...