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Comment: Re:Morons ... (Score 1) 190 190

So what you are saying is that they could incur legal bills to other people by knowingly using an invalid argument? In what way would that be a good outcome unless you are a lawyer? Have you ever heard of the term "chilling effect"? "Hey there, domain owner, you can either sell us your domainname for $1 or we'll start a frivolous lawsuit using this ridiculous and knowingly invalid claim which will cost you atleast $2,000 to defend against".

Comment: Re:How stupid could someone be? (Score 1) 111 111

Generation algorithms for software license keys is fine.
Simple generated keys stop casual sharing of licenses. Nothing stops dedicated hackers.
Why invest time and money in a very expensive license key system when all you're doing is providing the hackers with a more interresting challenge.
The problem here isn't generating keys, it's the relatively high chance of colission; it's badly generating keys.

Comment: Re:Kids don't understand sparse arrays (Score 1) 128 128

It all depends on what you want to do with your matrices. Various operations have various costs in different sparse matrix formats. The standard ones are COO or coordinate format: a list of triples (i, j, val); DOK or dictionary of keys format: the hashmap you are thinking of; LIL or list of lists format: a list for each row and a list if pairs (j, val) in each list entry; CSR/CSC or compact sparse row/column: an array of indices where each row starts, an array of column indices and an array of values.

COO and DOK are great for changing sparsity structure; LIL is very useful if you have a lot of row-wise (or column-wise) operations, or need to manipulate rows regularly. CSR is great for matrix operations such as multiplication, addition etc. You use what suits your usecase, or change between formats (relatively cheap) as needed.

"This is lemma 1.1. We start a new chapter so the numbers all go back to one." -- Prof. Seager, C&O 351