Finite-difference solution in the frequency domain
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tc-fdx.m:
      Matlab script generating file tc-fdx.dat
      with displacement in plane x3=z_max.
      The initial conditions are given in plane x3=z_min.
      Initial displacement
        ux0  = 1;
        uy0  = 0;
      Initial stress
        tx0  = -i*omega*beta*ux0;
        ty0  = 0;

tc-fdy.m:
      Matlab script generating file tc-fdy.dat
      with displacement in plane x3=z_max.
      The initial conditions are given in plane x3=z_min.
      Initial displacement
        ux0  = 0;
        uy0  = 1;
      Initial stress
        tx0  = 0;
        ty0  = -i*omega*beta*uy0;

tcsolver.m:
      Include file with Matlab script used by 'tc-fdx.m' and 'tc-fdy.m'.
      All 3 Matlab scripts should be located in the same directory.

The Matlab programs have no input files, all parametrers are defined in
the programs:
        z_min = 0;
        z_max = pi/b_const;
        b_const = 0.032;
        beta    = sqrt(6.0);
        gamma   = 0.15;
        theta   = 60*pi/180.;
      Elastic moduli at plane x3=z:
        fi    = b_const*z;
        a44   = beta^2*(1+2*gamma*sin(theta)^2*cos(fi)^2);
        a45   = 2*beta^2*gamma*sin(theta)^2*sin(fi)*cos(fi);
        a55   = beta^2*(1+2*gamma*sin(theta)^2*sin(fi)^2);
      Frequency domain:
        f_min = 0.001;
        f_max = 0.1;
        df    = 0.00025;
      and
        f_min = 0.1;
        f_max = 1.0;
        df    = 0.0025;

Form of files 'tc-fdx.dat' and 'tc-fdy.dat':
      column 1 ... frequency
      column 2 ... real      part of the x-component of the displacement
      column 3 ... imaginary part of the x-component of the displacement
      column 4 ... real      part of the y-component of the displacement
      column 5 ... imaginary part of the y-component of the displacement
      column 6 ... absolute value of the x-component of the displacement
      column 7 ... absolute value of the y-component of the displacement

The finite-difference solution in the frequency domain is compared with
the analytical solution by program tcfd.for.