Trigonometric Identities and Sums of Separable Functions
نویسندگان
چکیده
Modern computers have made commonplace many calculations that were impossible to imagine a few years ago. Still, when you face a problem with a high physical dimension, you immediately encounter the Curse of Dimensionality [1, p.94]. This curse is that the amount of computing power that you need grows exponentially with the dimension. The simplest manifestation of this curse appears when you try to represent a function by its sample values on a grid. If a function of one variable requires N samples, then an analogous function of n variables will need a grid of N samples. Thus, even relatively small problems in high dimensions are still unreasonably expensive. A method has been proposed in [2] to address this problem, based on approximating a function by a sum of separable functions:
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