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How to check if there exists a process with a given pid in Python?

... if the pid is not running, and do nothing otherwise. import os def check_pid(pid): """ Check For the existence of a unix pid. """ try: os.kill(pid, 0) except OSError: return False else: return True ...
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leading zeros in rails

...using a given padding character. str.rjust(integer, padstr=' ') → new_str If integer is greater than the length of str, returns a new String of length integer with str right justified and padded with padstr; otherwise, returns str. some_int = 5 some_int.to_s.rjust(2, '0') # => '05' ...
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How to avoid “Permission denied” when using pip with virtualenv

...ed Oct 19 '13 at 23:02 sebastian_oesebastian_oe 6,63822 gold badges1515 silver badges2020 bronze badges ...
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Check for internet connection availability in Swift

...unc isConnectedToNetwork() -> Bool { var zeroAddress = sockaddr_in(sin_len: 0, sin_family: 0, sin_port: 0, sin_addr: in_addr(s_addr: 0), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0)) zeroAddress.sin_len = UInt8(sizeofValue(zeroAddress)) zeroAddress.sin_family = sa_family_t(AF_INET)...
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How to randomize (or permute) a dataframe rowwise and columnwise?

...] 1 0 0 1 0 [4,] 0 0 1 0 1 To explain the call: out <- permatswap(mat, times = 99, burnin = 20000, thin = 500, mtype = "prab") times is the number of randomised matrices you want, here 99 burnin is the number of swaps made before we start taking random samples....
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How does the MapReduce sort algorithm work?

... 1 sampled keys that define the key range for each reduce. In particular, all keys such that sample[i − 1] <= key < sample[i] are sent to reduce i. This guarantees that the output of reduce i are all less than the output of reduce i+1." So their trick is in the way they determine the keys ...
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How can I pretty-print JSON using Go?

...NewFormatter() f.Indent = 4 // Marshall the Colorized JSON s, _ := f.Marshal(obj) fmt.Println(string(s)) } I'm writing the documentation for it now but I was excited to share my solution. share | ...
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What is the difference between UTF-8 and ISO-8859-1?

...e points of the Unicode character set, whereas UTF-8 can be used to encode all code points. At physical encoding level, only codepoints 0 - 127 get encoded identically; code points 128 - 255 differ by becoming 2-byte sequence with UTF-8 whereas they are single bytes with Latin-1. ...
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jQuery table sort

... If you want to avoid all the bells and whistles then may I suggest this simple sortElements plugin. Usage: var table = $('table'); $('.sortable th') .wrapInner('<span title="sort this column"/>') .each(function(){ var th ...
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How can I force a long string without any blank to be wrapped?

... Place zero-width spaces at the points where you want to allow breaks. The zero-width space is ​ in HTML. For example: ACTGATCG​AGCTGAAG​CGCAGTGC​GATGCTTC​GATGATGC ...