On Fri, Jul 08, 2005 at 03:33:16PM +0200, Henning Thielemann wrote:
On Thu, 7 Jul 2005, David Roundy wrote:
On the other hand, this is sort of a silly debate, since the API *I* want is a subset of the API *you* want.
The API you want is certainly not just a subset of what I want. E.g. the singular value decomposition in your favorite API will probably return a 1xN matrix or a MxN diagonal matrix containing the singular values, while with my favorite API it will return a vector or a list. Right?
I don't particularly care what API you use for svd, since it's trivial to convert from one API to the other. It's matrix arithmetic I care about, since that's the complicated part of the API. On the other hand, the most natural return value for svd would be a diagonal matrix, since that is what the objects are, right? svd returns three matrices, which when multiplied together give the original matrix... or at least that's how I think of it. But I'll grant that a diagonal matrix isn't the most convenient representation, and certain is far from the most efficient, unless we introduce a diagonal matrix constructor (which would certainly be nice). I guess you'd prefer that svd returns a list of doubles and two lists of vectors? Or a list of triplets of a double and two vectors? (Answering another email...) I certainly agree that fft is not a function of a matrix. -- David Roundy