/* Last updated: September 8, 2020 by Hereman in Boulder */ /* Data file s-NLS-run0-Sep8-2020.dat for the Nonlinear Schrodinger (NLS) equation. */ /* Generating the 20 determining equations in one run (which could be a bit slow for large systems). */ /* Took about 10 seconds on my 2012 Dell Latitude E6440 laptop */ /* NLS equation : i u_t + u_xx + a*|u|^2 u = 0. */ /* Set u = u[1] + i u[2], split in real and imaginary parts gives the system: */ /* u[1]_t + u[2]_xx + a*(u[1]^2+u[2]^2) u[2] = 0, */ /* u[2]_t - u[1]_xx - a*(u[1]^2+u[2]^2) u[1] = 0. */ /* Assign x[1] to x, x[2] to t, a is a real parameter to capture the focusing and defocusing NLS eqs. */ /* Solution of the determining equations is given in my paper: */ /* W. Hereman, Review of symbolic software for Lie symmetry analysis, */ /* Mathematical and Computer Modelling, 25(8-9), pp. 115-132 (1997). */ /* DOI: 10.1016/S0895-7177(97)00063-0. */ /* number of independent variables: */ p : 2 $ /* number of dependent variables: */ q : 2 $ /* number of equations in the system: */ m : 2 $ parameters:[a]$ sublisteqs:[all]$ subst_deriv_of_vi:true$ highest_derivatives:all$ warnings:true$ /* no information is given yet -- set "true" when information is given */ info_given:false$ e1 : u[1,[0,1]]+a*(u[1]^2+u[2]^2)*u[2]+u[2,[2,0]]; e2 : u[2,[0,1]]-a*(u[1]^2+u[2]^2)*u[1]-u[1,[2,0]]; v1 : u[1,[0,1]]; v2 : u[2,[0,1]]; /* end of command file s-NLS-run0-Sep8-2020.dat */