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R - Concatenate two dataframes?
...olumn b to data frame b.
Results
> a <- data.frame(a=c(0,1,2), b=c(3,4,5), c=c(6,7,8))
> a
a b c
1 0 3 6
2 1 4 7
3 2 5 8
> b <- data.frame(a=c(9,10,11), c=c(12,13,14))
> b
a c
1 9 12
2 10 13
3 11 14
> b$b <- NA
> b
a c b
1 9 12 NA
2 10 13 NA
3 11 14 NA
> ...
Handling very large numbers in Python
...nterpreter will automatically use whichever is more appropriate. In Python 3.0+, the int type has been dropped completely.
That's just an implementation detail, though — as long as you have version 2.5 or better, just perform standard math operations and any number which exceeds the boundaries of...
Checking for the correct number of arguments
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3 Answers
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In HTML I can make a checkmark with ✓ . Is there a corresponding X-mark?
Is there a corresponding X mark to ✓ ( &#x2713; )? What is it?
4 Answers
4
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How to hash a string into 8 digits?
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answered Apr 15 '13 at 6:17
Raymond HettingerRaymond Hettinger
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Using Rails 3.1 assets pipeline to conditionally use certain css
I’m in the process of building my first solo Rails app using Rails 3.1.rc5. My problem is that I want to have my site render the various CSS files conditionally. I’m using Blueprint CSS and I’m trying to have sprockets/rails render screen.css most of the time, print.css only when printing,...
Performance of foreach, array_map with lambda and array_map with static function
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3 Answers
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How can I add items to an empty set in python
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3 Answers
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Bootstrap carousel multiple frames at once
This is the effect I'm trying to achieve with Bootstrap 3 carousel
14 Answers
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How to re-raise an exception in nested try/except blocks?
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As of Python 3 the traceback is stored in the exception, so a simple raise e will do the (mostl...