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Possible reasons for timeout when trying to access EC2 instance
I cannot SSH into my instance - Operation timed out. What could be the reasons why, and what can I do to resolve it? Rebooting normally takes a long time to take effect, and might just makes things worst
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Google Maps: how to get country, state/province/region, city given a lat/long value?
I need a list of countries, states & cities based on a collection of lat/long values I have. I need to store this information in a manner that hierarchy is preserve and without duplicates (e.g. "USA" and "United States" and "United States of America" are the same country; I only want one instance of...
How to include “zero” / “0” results in COUNT aggregate?
I've just got myself a little bit stuck with some SQL. I don't think I can phrase the question brilliantly - so let me show you.
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Catching error codes in a shell pipe
I currently have a script that does something like
4 Answers
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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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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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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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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 is “=default” different from “{}” for default constructor and destructor?
I originally posted this as a question only about destructors, but now I'm adding consideration of the default constructor. Here's the original question:
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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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