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Best way to test if a generic type is a string? (C#)
I have a generic class that should allow any type, primitive or otherwise. The only problem with this is using default(T) . When you call default on a value type or a string, it initializes it to a reasonable value (such as empty string). When you call default(T) on an object, it returns null. Fo...
Why can't I use float value as a template parameter?
When I try to use float as a template parameter, the compiler cries for this code, while int works fine.
11 Answers
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SQL Server: Filter output of sp_who2
Under SQL Server, is there an easy way to filter the output of sp_who2? Say I wanted to just show rows for a certain database, for example.
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What is the proper way to comment functions in Python?
Is there a generally accepted way to comment functions in Python? Is the following acceptable?
10 Answers
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Grouped LIMIT in PostgreSQL: show the first N rows for each group?
I need to take the first N rows for each group, ordered by custom column.
5 Answers
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How to find and return a duplicate value in array
arr is array of strings:
20 Answers
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dplyr: “Error in n(): function should not be called directly”
I am attempting to reproduce one of the examples in the dplyr package but am getting this error message. I am expecting to see a new column n produced with the frequency of each combination. What am I missing? I triple checked that the package is loaded.
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techniques for obscuring sensitive strings in C++
I need to store sensitive information (a symmetric encryption key that I want to keep private) in my C++ application. The simple approach is to do this:
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Negative weights using Dijkstra's Algorithm
I am trying to understand why Dijkstra's algorithm will not work with negative weights. Reading an example on Shortest Paths , I am trying to figure out the following scenario:
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