Spectral methods [1] are FE-like methods with non-zero basis functions over the whole domain. Indeed they produce full matrices. [1] http://en.wikipedia.org/wi

Spectral methods [1] are FE-like methods with non-zero basis functions over the whole domain. Indeed they produce full matrices. [1] http://en.wikipedia.org/wiki/Spectral_method http://en.wikipedia.org/wiki/Spectral_method