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How to check if a map contains a key in Go?
...ring) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" is indeed present in the map, the body of the if statement will be executed and val will be local to that scope.
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Dashed line border around UIView
...t@2x.png and test@3x.png with size of 240x240 and 360x360 which is used in all the apple device automatically with it's related name. (i.e. test.png is use in iPhone 4, test@2x will useful for iPhone 4s, 5, 5s, 6, 6s and twst@3x will useful for iPhone 6 plus, 6s plus.
– Paras J...
Print multiple arguments in Python
...or", name, "is", score)
If you don't want spaces to be inserted automatically by print in the above example, change the sep parameter:
print("Total score for ", name, " is ", score, sep='')
If you're using Python 2, won't be able to use the last two because print isn't a function in Python 2. Y...
What is the difference between 'my' and 'our' in Perl?
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On the other hand, our variables are package variables, and thus automatically:
global variables
definitely not private
not necessarily new
can be accessed outside the package (or lexical scope) with the
qualified namespace, as $package_name::variable.
Declaring a variable with our allows you...
Remove characters except digits from string using Python?
How can I remove all characters except numbers from string?
15 Answers
15
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C# binary literals
... @Dai that’s no different than hex literals. In other words, all constants are big endian, but stored little endian on Intel/AMD and most ARMs. 0xDEADBEEF will be stored as 0xEF 0xBE 0xAD 0xDE
– Cole Johnson
Sep 2 '19 at 18:28
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Convert objective-c typedef to its string equivalent
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This is really a C question, not specific to Objective-C (which is a superset of the C language). Enums in C are represented as integers. So you need to write a function that returns a string given an enum value. There are many ways to...
Dynamically updating plot in matplotlib
...out the more modern animation examples in the matplotlib documentation. Finally, the animation API defines a function FuncAnimation which animates a function in time. This function could just be the function you use to acquire your data.
Each method basically sets the data property of the object be...
Circular list iterator in Python
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Output:
a b c a b c ...
(Loops forever, obviously)
In order to manually advance the iterator and pull values from it one by one, simply call next(pool):
>>> next(pool)
'a'
>>> next(pool)
'b'
share...
Transposing a NumPy array
...of a 1D array is still a 1D array! (If you're used to matlab, it fundamentally doesn't have a concept of a 1D array. Matlab's "1D" arrays are 2D.)
If you want to turn your 1D vector into a 2D array and then transpose it, just slice it with np.newaxis (or None, they're the same, newaxis is just mor...