def dm_dalton_ppm(calculated_mass, experimental_mass):
    """ 
    Difference in dalton and ppm 
    
    Parameters
    ----------
    calculated_mass: int
        calculated mass of peptide sequence
        
    experimental_mass: int
        experimental mass of peptide sequence
   
    Returns
    -------
    tuple
        delta in ppm and delta in dalton
    """
    
    dm_dalton = calculated_mass - experimental_mass
    dm_ppm = (dm_dalton/calculated_mass)*1000000.0
    return dm_dalton, dm_ppm