def METHOD_NAME(filename):
    # Array gen {
    with open(filename, "wt") as f:
        # Only the first column name matters.
        # The others are required but otherwise ignored.
        f.write("density c2 c3 c4 c5 c6 c7 c8\n")
        nx = 8
        ny = 10
        for iy in range(ny):
            y = float(iy)
            for ix in range(nx):
                x = float(ix)
                dist = math.sqrt(x*x + y*y)
                if (ix < nx - 1):
                   f.write("%g " % dist)
                else:
                   f.write("%g\n" % dist)
    # Array gen }