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Convert columns to string in Pandas
I have the following DataFrame from a SQL query:
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Many-to-many relationship with the same model in rails?
How can I make a many-to-many relationship with the same model in rails?
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pandas: How do I split text in a column into multiple rows?
I'm working with a large csv file and the next to last column has a string of text that I want to split by a specific delimiter. I was wondering if there is a simple way to do this using pandas or python?
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What is the difference between a string and a byte string?
I am working with a library which returns a byte string and I need to convert this to a string.
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Why do I need 'b' to encode a string with Base64?
Following this python example , I encode a string as Base64 with:
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How to get the first non-null value in Java?
Is there a Java equivalent of SQL's COALESCE function? That is, is there any way to return the first non-null value of several variables?
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Why does string::compare return an int?
Why does string::compare return an int instead of a smaller type like short or char ? My understanding is that this method only returns -1, 0 or 1.
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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 do I detect unsigned integer multiply overflow?
I was writing a program in C++ to find all solutions of a b = c , where a , b and c together use all the digits 0-9 exactly once. The program looped over values of a and b , and it ran a digit-counting routine each time on a , b and ab to check if the digits condition was satisfied.
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I want to get the type of a variable at runtime
I want to get the type of a variable at runtime.
How do I do this?
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