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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 are multi-dimensional arrays formatted in memory?
In C, I know I can dynamically allocate a two-dimensional array on the heap using the following code:
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How do I put two increment statements in a C++ 'for' loop?
I would like to increment two variables in a for -loop condition instead of one.
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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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Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
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Does pandas iterrows have performance issues?
I have noticed very poor performance when using iterrows from pandas.
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Is a Python list guaranteed to have its elements stay in the order they are inserted in?
If I have the following Python code
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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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Create a pointer to two-dimensional array
I need a pointer to a static 2-dimensional array. How is this done?
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Sending a message to nil in Objective-C
As a Java developer who is reading Apple's Objective-C 2.0 documentation: I wonder what " sending a message to nil " means - let alone how it is actually useful. Taking an excerpt from the documentation:
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