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Converting between datetime, Timestamp and datetime64

...amp(ts) datetime.datetime(2012, 12, 4, 19, 51, 25, 362455) >>> np.__version__ '1.8.0.dev-7b75899' The above example assumes that a naive datetime object is interpreted by np.datetime64 as time in UTC. To convert datetime to np.datetime64 and back (numpy-1.6): >>> np.datetime6...
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Is there a way to access method arguments in Ruby?

...meters # => [[:req, :x], [:req, :y]] You can use the special variable __method__ to get the name of the current method. So within a method the names of its parameters can be obtained via args = method(__method__).parameters.map { |arg| arg[1].to_s } You could then display the name and value ...
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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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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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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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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 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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What are the calling conventions for UNIX & Linux system calls (and user-space functions) on i386 an

...rameters for Linux system call are passed using registers. %eax for syscall_number. %ebx, %ecx, %edx, %esi, %edi, %ebp are used for passing 6 parameters to system calls. The return value is in %eax. All other registers (including EFLAGS) are preserved across the int $0x80. I took following snipp...
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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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Is there a way to instantiate objects from a string holding their class name?

...ce() { return new T; } typedef std::map<std::string, Base*(*)()> map_type; map_type map; map["DerivedA"] = &createInstance<DerivedA>; map["DerivedB"] = &createInstance<DerivedB>; And then you can do return map[some_string](); Getting a new instance. Another idea is ...