Simulations of a two-dimensional, isothermal shock tube with RBV2 (solid lines), PLUTO (dashed lines), and Dedalus (dotted lines). Decreasing transparency indicates more advanced simulation time, plotted at 0.00, 0.01, and 0.02 sound-crossing times. The computational domain is a 200 × 200 mesh that spans ﹩(-0.5,0.5)﹩ and ﹩(-0.5,0.5)﹩ with an initial density contrast of ﹩0.6﹩ and a sound speed c_s = 1.0.