BeginPackage ["HarmonicOscillator'"]
											HarmonicOscillator: : usage =
											"HarmonicOscillator' is a package that provides
											functions for the eigenenergies and normalized energy
											eigenfunctions of the simple harmonic oscillator."
											φ: : usage = "φ[n, x] gives the normalized energy
											eigenfunctions of the simple harmonic oscillator."
											ε: : usage = "ε[n] gives the eigenenergies of
											the simple harmonic oscillator in terms of ћω."
											ω: : usage = "The symbol  ω stands for the oscillator frequency."
											m: : usage = "The symbol m stands for the mass."
											ћ: : usage=
											"The symbol ћ stands for h/2π with h being Planck's counstant."
											Begin ["'Private'"]
											HarmonicOscillator: :badarg=
											"You called '1' with '2' argument (s) !
											It must have '3' argument (s)."
											φ: :quannum =
											"The quantum number must be a nonnegative integer. your
											quantum number '1' is not allowed."
											ε: :badarg =
											"The argument must be a nonnegative integer. You entered '1'."
											φ[n_Integer? NonNegative, x_]: =
											((2^ (–/2)) (n ! ^ (–1/2)) (((mω) / (ћπ)) ^ (1/4))
											HermiteH [n, Sqrt [mω/ћ]x]Exp [– ((mω) / (2ћ))x^2]}
											φ[n_, x_] : = Message [φ: :quannum, {n}]
											φ [arg _ _ _ / ; Length [{arg]] ≠ 2] : =
											Message [HarmonicOscillator: :badarg, φ, Length [{arg}], 2]
											ε[n_Integer ? NonNegative] : = ћω (n + 1/2))
											ε[arg_]: = Message [ε: :badarg, {arg}]
											ε[arg_ _ _/ ; (Length [{arg}] ≠1)] : =
											Message [HarmonicOscillator: :badarg, ε, Length [{arg}], 1]
											End[]
											Protect [φ, ε]
											EndPackage[]