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Preferred way to create a Scala list

...end is O(1). – Daniel C. Sobral Aug 31 '15 at 19:33 @pgoggijr That is not true. First, there's no "change" anywhere, b...
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Most efficient way of making an if-elif-elif-else statement when the else is done the most?

...: the_thing = 2 elif something == 'there': the_thing = 3 else: the_thing = 4 2.py something = 'something' options = {'this': 1, 'that': 2, 'there': 3} for i in xrange(1000000): the_thing = options.get(something, 4) 3.py something = 'something' options = {'t...
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How to extract a floating number from a string [duplicate]

I have a number of strings similar to Current Level: 13.4 db. and I would like to extract just the floating point number. I say floating and not decimal as it's sometimes whole. Can RegEx do this or is there a better way? ...
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Clang vs GCC - which produces faster binaries? [closed]

...(speed, memory footprint, reliability) of binaries it produces - if gcc -O3 can produce a binary that runs 1% faster, or Clang binaries take up more memory or just fail due to compiler bugs, it's a deal-breaker. ...
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Getting a map() to return a list in Python 3.x

... Do this: list(map(chr,[66,53,0,94])) In Python 3+, many processes that iterate over iterables return iterators themselves. In most cases, this ends up saving memory, and should make things go faster. If all you're going to do is iterate over thi...
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how to solve “ruby installation is missing psych” error?

I used rvm to install ruby 1.9.3. even though it was successfully installed, it complained about libyaml. and now every time i wanna install a gem (say rails) this warning shows up: ...
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How to get one value at a time from a generator function in Python?

... answered Mar 10 '10 at 19:13 Ignacio Vazquez-AbramsIgnacio Vazquez-Abrams 668k127127 gold badges11911191 silver badges12501250 bronze badges ...
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Fast permutation -> number -> permutation mapping algorithms

I have n elements. For the sake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements. ...
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Comparing two dictionaries and checking how many (key, value) pairs are equal

... | edited Jun 14 '18 at 13:15 Olivier Melançon 17.9k33 gold badges3232 silver badges5555 bronze badges ...
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WARN Could not determine content-length of response body. Set content-length of the response or set

I just upgraded to rails 3.2.2, and now on rails s, page load, I get all these errors in the log: 3 Answers ...