program inf_square_well
        implicit none

        real :: start, finish = 1.0
        real, parameter :: a = 10.0
        integer, parameter :: waves = 200
        real, parameter :: coeff = sqrt(2/a)
        real :: wavefunction(waves)
        integer :: x = 0
        integer :: n = 1
        character(len = 200) :: filename
        real, parameter :: pi = 3.141592653589793
        integer, parameter :: steps = 10

        call cpu_time(start)

        do x = 0, steps, 1
                do n = 1, waves, 1
                        wavefunction(n) = coeff*sin(n*pi*(x*(a/steps))/a)
                        write(filename, "('Data/wavefunction',I3.3,'.dat')") n
                        open(n + 20, file = filename, position = "append")
                        write(n + 20, 1) (x*(a/steps)), wavefunction(n)
                        close(n + 20)
                end do
        end do

        call cpu_time(finish)
        print*, "The program took ", finish - start, " seconds to run."

        1 format(F25.20, F25.20)
end program inf_square_well