The Factorial Function is a classic interview question. It opens the doors to a discussion about stack overflow (if done recursively) and integer overflow (if the param is too large) as well as discussions around how to handle and catch errors. Here is one way to do it using recursion: static Int64 Factorial...
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When writing a text classification system you need to train it. Typically you have a corpus of good data that has been accurately pre-classified and this is what you throw at the system while it is learning the classification. I came up with what I thought was a good analogy for an untrained text classifier...
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I'm currently working on a text classification system. This is requiring a fair amount of research and background reading so I'm going to create a list of references that I'm using: A Plan for Spam by Paul Graham Better Bayesian Filtering by Paul Graham Bayesian Filtering: Beyond Binary Classification...
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I was wondering if the 16 digits that most credit cards have (VISA and Mastercard et al) if you don't include American Express' 13 digit cards were enough for the world or if we'd run out of digits at some point. If I've done my calculations correctly and based on my assumption that there are 7 billion...
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I'm working on a project at the moment that involves the verification of credit card numbers. This has led to running checksums on the numbers to validate them including Luhn's algorithm. Simply stated, Luhn's algorithm doubles every second digit (starting from the right) and then adds together all of...
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