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Are members of a C++ struct initialized to 0 by default?
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edited Jul 1 '09 at 15:05
answered Jul 1 '09 at 15:00
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How do I check if there are duplicates in a flat list?
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14 Answers
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How do I trim leading/trailing whitespace in a standard way?
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Can dplyr package be used for conditional mutating?
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Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with i...
How to determine the longest increasing subsequence using dynamic programming?
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19 Answers
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How to change navbar collapse threshold using Twitter bootstrap-responsive?
I'm using Twitter Bootstrap 2.0.1 in a Rails 3.1.2 project, implemented with bootstrap-sass. I'm loading both the bootstrap.css and the bootstrap-responsive.css files, as well as the bootstrap-collapse.js Javascript.
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How to take column-slices of dataframe in pandas
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10 Answers
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If vs. Switch Speed
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The compiler can build jump tables where applicable. For example, when you use the reflector t...
What is the difference between quiet NaN and signaling NaN?
...FPU. Whether the exception is thrown depends on the state of the FPU.
C++11 adds a few language controls over the floating-point environment and provides standardized ways to create and test for NaNs. However, whether the controls are implemented is not well standardized and floating-point except...
Converting a column within pandas dataframe from int to string
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In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
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