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CSS media queries: max-width OR max-height
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answered Jul 9 '12 at 23:40
Fabrizio CalderanFabrizio Calderan
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Use of the MANIFEST.MF file in Java
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FrankFrank
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How do I (or can I) SELECT DISTINCT on multiple columns?
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451
SELECT DISTINCT a,b,c FROM t
is roughly equivalent to:
SELECT a,b,c FROM t GROUP BY a,b,c...
Why does struct alignment depend on whether a field type is primitive or user-defined?
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4 Answers
4
Active
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RESTful Alternatives to DELETE Request Body
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4 Answers
4
Active
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Relative frequencies / proportions with dplyr
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mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes it easy to prog...
How do I terminate a thread in C++11?
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Howard HinnantHoward Hinnant
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What Makes a Method Thread-safe? What are the rules?
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4 Answers
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What is two way binding?
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McGarnagleMcGarnagle
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How to check a string for specific characters?
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print('Found')
else
print('Not found')
... or
chars = set('0123456789$,')
if any((c in chars) for c in s):
print('Found')
else:
print('Not Found')
[Edit: added the '$' in s answers]
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