CALLIOPE: Pseudospectral Shearing Magnetohydrodynamics Code with a Pencil Decomposition

The pseudospectral method is a highly accurate numerical scheme suitable for turbulence simulations. We have developed an open-source code, \textsc{\textsf{Calliope}}, which adopts the P3DFFT library \citep{Pekurovsky2012} to perform fast Fourier transform with two-dimensional (pencil) decomposition of grids. \textsc{\textsf{Calliope}} can solve incompressible magnetohydrodynamics (MHD), isothermal compressible MHD, and rotational reduced MHD parallel computation using very large numbers cores ($> 10^5$ $2048^3$ grids). code also local magnetorotational in shearing frame remapping \citep{Rogallo1981,Umurhan2004}. currently only that compute pencil-domain decomposition. This paper presents results linear nonlinear tests, including largest grid number reported date.