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Any reason not to use '+' to concatenate two strings?
... Tuple would be faster - the code was just an example :) Usually long multiple string inputs are dynamic.
– Mikko Ohtamaa
Apr 6 '12 at 12:52
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How to generate a random string in Ruby
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(0...8).map { (65 + rand(26)).chr }.join
I spend too much time golfing.
(0...50).map { ('a'..'z').to_a[rand(26)] }.join
And a last one that's even more confusing, but more flexible and wastes fewer cycles:
o = [('a'..'z'), ('A'..'Z')].map(&:to_a...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...
I found a faster way to solve the problem, at least on realistically large datasets using:
df.set_index(KEY).to_dict()[VALUE]
Proof on 50,000 rows:
df = pd.DataFrame(np.random.randint(32, 120, 100000).reshape(50000,2),columns=list('AB'))
df['A'] = df['A'].apply(chr)
%timeit dict(zip(df...
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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Evaluating a mathematical expression in a string
...p://pyparsing.wikispaces.com/message/view/home/15549426
'''
__note__ = '''
All I've done is rewrap Paul McGuire's fourFn.py as a class, so I can use it
more easily in other places.
'''
class NumericStringParser(object):
'''
Most of this code comes from the fourFn.py pyparsing example
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Remove non-utf8 characters from string
...eplacement is whatever was captured into group 1. This effectively removes all invalid bytes.
It is possible to repair the string, by encoding the invalid bytes as UTF-8 characters. But if the errors are random, this could leave some strange symbols.
$regex = <<<'END'
/
(
(?: [\x00-...
Convert Python dictionary to JSON array
...mpared to b64encode. For example, for the 256 character string s = ''.join(chr(i) for i in xrange(256)), len(json.dumps(b64encode(s))) == 346 vs len(json.dumps(s.decode('latin1'))) == 1045.
– martineau
Feb 2 '13 at 15:45
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filter for complete cases in data.frame using dplyr (case-wise deletion)
...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
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How to automatically convert strongly typed enum into int?
... edited Apr 10 '18 at 6:26
chr
10166 bronze badges
answered Oct 12 '15 at 14:06
Class SkeletonClass Skele...
What are the “standard unambiguous date” formats for string-to-date conversion in R?
...te (+1). However, the error message "standard unambiguous format" is ironically ambiguous, to which the 23 previous questions attest. A more direct error message like, "format not recognized, see documentation" might improve user experience. Also, I don't believe "01/01/2000" is ISO-8601 ("2000-01-0...