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Difference between String replace() and replaceAll()

What's the difference between java.lang.String 's replace() and replaceAll() methods, other than later uses regex? For simple substitutions like, replace . with / , is there any difference? ...
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Principal component analysis in Python

... Months later, here's a small class PCA, and a picture: #!/usr/bin/env python """ a small class for Principal Component Analysis Usage: p = PCA( A, fraction=0.90 ) In: A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
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What is the most accurate way to retrieve a user's correct IP address in PHP?

.... In a few minutes I will update the code. – Corey Ballou Jan 9 '10 at 13:37 35 -1 this is vulne...
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How to detect reliably Mac OS X, iOS, Linux, Windows in C preprocessor? [duplicate]

... Apple platform" #endif #elif __linux__ // linux #elif __unix__ // all unices not caught above // Unix #elif defined(_POSIX_VERSION) // POSIX #else # error "Unknown compiler" #endif The defined macros depend on the compiler that you are going to use. The _WIN64 #ifdef can be nes...
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Reset C int array to zero : the fastest way?

... long long int or unsigned long long int, what is the fastest way to reset all its content to zero (not only for initialization but to reset the content several times in my program)? Maybe with memset? ...
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How to convert JSON data into a Python object

...ry, the order of items will directly correspond.". Good to know for such small, local code blocks. I'd add a comment though to explicitly alert maintainers of code of such a dependency. – cfi Jun 1 '16 at 7:33 ...
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What are some (concrete) use-cases for metaclasses?

...a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plotting call. So to create both an interactive plotting wrapper and an offscreen plotting wrapper, I found it was more efficient to do this via metacla...
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How to pretty-print a numpy.array without scientific notation and with given precision?

...335 0.712] And suppress suppresses the use of scientific notation for small numbers: y=np.array([1.5e-10,1.5,1500]) print(y) # [ 1.500e-10 1.500e+00 1.500e+03] np.set_printoptions(suppress=True) print(y) # [ 0. 1.5 1500. ] See the docs for set_printoptions for other options. T...
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Why is `std::move` named `std::move`?

The C++11 std::move(x) function doesn't really move anything at all. It is just a cast to r-value. Why was this done? Isn't this misleading? ...
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How to add property to a class dynamically?

...ing on. Better late than never. You can add a property to a class dynamically. But that's the catch: you have to add it to the class. >>> class Foo(object): ... pass ... >>> foo = Foo() >>> foo.a = 3 >>> Foo.b = property(lambda self: self.a + 1) >>&...