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Read-only and non-computed variable properties in Swift

...property which returns that property: public class Clock { private var _hours = 0 public var hours: UInt { return _hours } } But this can be achieved in a different, shorter way, as stated in the section "Access Control" of the "The Swift Programming Language" book: public class Clo...
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How can I hash a password in Java?

...m recommended cost, used by default */ public static final int DEFAULT_COST = 16; private static final String ALGORITHM = "PBKDF2WithHmacSHA1"; private static final int SIZE = 128; private static final Pattern layout = Pattern.compile("\\$31\\$(\\d\\d?)\\$(.{43})"); private final Se...
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Find out time it took for a python script to complete execution

...test function" L = [] for i in range(100): L.append(i) if __name__=='__main__': from timeit import Timer t = Timer("test()", "from __main__ import test") print t.timeit() Then to convert to minutes, you can simply divide by 60. If you want the script runtime in an easi...
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What is getattr() exactly and how do I use it?

...answered Apr 10 '19 at 9:42 blue_noteblue_note 21k55 gold badges3737 silver badges6262 bronze badges ...
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Assigning a variable NaN in python without numpy

...e 1, in <module> File "C:\Python35\lib\fractions.py", line 146, in __new__ numerator) ValueError: Invalid literal for Fraction: 'nan' >>> >>> Fraction(float('nan')) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "C:\Python35\...
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Efficient way to apply multiple filters to pandas DataFrame or Series

...turn op(x[col],n) In [15]: def f(x, *b): return x[(np.logical_and(*b))] In [16]: b1 = b(df, 'col1', ge, 1) In [17]: b2 = b(df, 'col1', le, 1) In [18]: f(df, b1, b2) Out[18]: col1 col2 1 1 11 Update: pandas 0.13 has a query method for these kind of use cases, assuming c...
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How is a CRC32 checksum calculated?

... 1100001010 = Quotient (nobody cares about the quotient) _______________ 10011 ) 11010110110000 = Augmented message (1101011011 + 0000) =Poly 10011,,.,,.... -----,,.,,.... 10011,.,,.... 10011,.,,.... -----,.,,.... 00001.,,.... ...
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How to do Base64 encoding in node.js?

...wered May 31 '11 at 2:46 onteria_onteria_ 57.1k66 gold badges6363 silver badges6060 bronze badges ...
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Converting integer to string in Python

... string is done with the builtin str() function, which basically calls the __str__() method of its parameter. share | improve this answer | follow | ...
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How do I do base64 encoding on iOS?

...ve posted it here: First, you need the mapping tables: static const char _base64EncodingTable[64] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; static const short _base64DecodingTable[256] = { -2, -2, -2, -2, -2, -2, -2, -2, -2, -1, -1, -2, -1, -1, -2, -2, -2, -2, -...