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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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Why does struct alignment depend on whether a field type is primitive or user-defined?
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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...
Use of the MANIFEST.MF file in Java
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FrankFrank
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RESTful Alternatives to DELETE Request Body
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What Makes a Method Thread-safe? What are the rules?
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How do I terminate a thread in C++11?
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Howard HinnantHoward Hinnant
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What is two way binding?
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McGarnagleMcGarnagle
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Why is a round-trip conversion via a string not safe for a double?
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*dst = 0;
}
}
It turns out that _ecvt returns the string 845512408225570.
Notice the trailing zero? It turns out that makes all the difference!
When the zero is present, the result actually parses back to 0.84551240822557006, which is your original number -- so it compares equal, a...
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...