Consider a file file.txt having the form

# First line is a grid of y; Starting from second line: first number is a, second is temperature, next is set of numbers is corresponding to f(y) on the grid
0.000000e+00    0.000000e+00    0.000000e+00    2.500000e-01    5.000000e-01
0.100000e+00    0.000000e+01    0.010000e+02    2.500000e-02    5.000000e-02

How to convert it to a form

0.000000e+00    0.000000e+00    0.000000e+00    2.500000e-01    5.000000e-01
0.100000e+00    0.000000e+01    0.010000e+02    2.500000e-02    5.000000e-02