An approach for the fast analysis of “irregular”, i.e., of conformal, periodic or aperiodic, 2D arrays, based on the use of the p-series approach and Non-Uniform FFT (NUFFT) routines is proposed to restore the asymptotic growth of the computing time to that of few, standard FFTs. A sub-array partition strategy is also sketched and shown to further unburden the procedure and controlling the accuracy. The approach has been implemented in both, sequential and parallel codes, enabling its execution on CPUs and on cost-effective, massively parallel computing platforms as Graphic Processing Units (GPUs). Its performance in terms of computational efficiency and accuracy has been assessed also against benchmarks provided by algorithms based on fast...