“…The second objective of the proposed method is to present new applications of Ooura's methods (Ooura, 2001(Ooura, , 2005 for the Fourier transforms to obtain the solution of PIDEs. The high accuracy of the proposed method is due to the very fast convergence of Ooura's methods, and speeding up of computations by Ooura's methods is realized by combining them with the nonuniform FFT (Dutt & Rokhlin, 1993, 1995Greengard & Lee, 2004;Potts et al, 2001;Steidl, 1998) or the fractional FFT (Bailey & Swarztrauber, 1991;Chourdakis, 2005;Tanaka, 2014a). In addition, in order to treat a (seemingly) singular integral in (1.10), we propose an indefinite integration formula using the sinc-Gauss sampling formula (Tanaka et al, 2008), which is also accurate and combined with the FFT.…”