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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
When using summarise with plyr 's ddply function, empty categories are dropped by default. You can change this behavior by adding .drop = FALSE . However, this doesn't work when using summarise with dplyr . Is there another way to keep empty categories in the result?
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Putting text in top left corner of matplotlib plot
How can I put text in the top left (or top right) corner of a matplotlib figure, e.g. where a top left legend would be, or on top of the plot but in the top left corner? E.g. if it's a plt.scatter(), then something that would be within the square of the scatter, put in the top left most corner.
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Catching error codes in a shell pipe
I currently have a script that does something like
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ActiveRecord: size vs count
In Rails, you can find the number of records using both Model.size and Model.count . If you're dealing with more complex queries is there any advantage to using one method over the other? How are they different?
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how to set “camera position” for 3d plots using python/matplotlib?
I'm learning how to use mplot3d to produce nice plots of 3d data and I'm pretty happy so far. What I am trying to do at the moment is a little animation of a rotating surface. For that purpose, I need to set a camera position for the 3D projection. I guess this must be possible since a surface can b...
What does multicore assembly language look like?
Once upon a time, to write x86 assembler, for example, you would have instructions stating "load the EDX register with the value 5", "increment the EDX" register, etc.
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How to normalize an array in NumPy?
I would like to have the norm of one NumPy array. More specifically, I am looking for an equivalent version of this function
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How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
...rent version of ruby is ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.5.0] but I want to update it to the latest patch level using rvm. How can I do this?
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~x + ~y == ~(x + y) is always false?
Does this code always evaluate to false? Both variables are two's complement signed ints.
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Fastest way to remove first char in a String
Say we have the following string
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