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Should I use a data.frame or a matrix?
When should one use a data.frame , and when is it better to use a matrix ?
6 Answers
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Pandas convert dataframe to array of tuples
I have manipulated some data using pandas and now I want to carry out a batch save back to the database. This requires me to convert the dataframe into an array of tuples, with each tuple corresponding to a "row" of the dataframe.
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Breadth First Vs Depth First
When Traversing a Tree/Graph what is the difference between Breadth First and Depth first? Any coding or pseudocode examples would be great.
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Using boolean values in C
C doesn't have any built-in boolean types. What's the best way to use them in C?
18 Answers
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Query for array elements inside JSON type
I'm trying to test out the json type in PostgreSQL 9.3.
I have a json column called data in a table called reports . The JSON looks something like this:
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Rails 3: I want to list all paths defined in my rails application
I want to list all defined helper path functions (that are created from routes) in my rails 3 application, if that is possible.
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Evaluating a mathematical expression in a string
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11 Answers
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WAMP/XAMPP is responding very slow over localhost
I don't know what the problem is. WAMP was very slow, so I reformatted my computer and installed WAMP. Still, accessing localhost is very, very slow, and sometimes it doesn't even load at all. I even removed it and replaced it with XAMPP, but I still got the same result. What might possibly be the p...
Can PostgreSQL index array columns?
I can't find a definite answer to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?
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How to generate string of a certain length to insert into a file to meet a file size criteria?
I have a requirement to test some load issues with regards to file size. I have a windows application written in C# which will automatically generate the files. I know the size of each file, ex. 100KB, and how many files to generate. What I need help with is how to generate a string less than or ...