select the couple of variables available. The flags which can be used are:
flag = 1 pH and CO2 given
flag = 2 CO2 and HCO3 given
flag = 3 CO2 and CO3 given
flag = 4 CO2 and ALK given
flag = 5 CO2 and DIC given
flag = 6
sys
0 if the manipulation is carried out in a system closed to the atmosphere or 1 if its is carried out in a system open to the atmosphere
var1
Value of the first variable in mol/kg, except for pH and for pCO2 in $\mu$atm
var2
Value of the second variable in mol/kg, except for pH
pCO2a
CO2 partial pressure in the atmosphere $pCO_2$ in $$atm. It is only used in systems open to the atmosphere (i.e. when sys=1)co3{Amount of $CO_3^{2-}$ added in $mol\,kg^{-1}$}
hco3{Amount of $HCO_3^{2-}$ added in $mol\