addMolecules             package:Rdisop             R Documentation

_A_d_d/_s_u_b_t_r_a_c_t _s_u_m _f_o_r_m_u_l_a_e

_D_e_s_c_r_i_p_t_i_o_n:

     Simple arithmetic modifications of sum formulae.

_U_s_a_g_e:

     addMolecules(formula1, formula2, elements = NULL)
     subMolecules(formula1, formula2, elements = NULL)

_A_r_g_u_m_e_n_t_s:

formula1: Sum formula

formula2: Sum formula

elements: list of allowed chemical elements, defaults to full periodic
          system of elements

_D_e_t_a_i_l_s:

     addMolecules() adds the second argument to the first.
     subMolecules() subtracts the second argument from the first.

     This can be useful to revert e.g. adduct/fragment formation found
     in ESI mass spectrometry, or to mimick simple chemical reactions.
     No chemical checks are performed.

_V_a_l_u_e:

        : A list with the elements

     _f_o_r_m_u_l_a repeated sum formula

     _m_a_s_s exact mass of molecule 

     _s_c_o_r_e dummy value, always 1.0 

     _i_s_o_t_o_p_e_s a list of isotopes 

_A_u_t_h_o_r(_s):

     Steffen Neumann <sneumann@IPB-Halle.DE>

_E_x_a_m_p_l_e_s:

     # For proton-Adduct of Ethanol:
     subMolecules("C2H7O", "H")

