GET_BALANCE_RG1 is a standard SAP function module available within R/3 SAP systems depending on your version and release level. Below are the pattern details for this FM showing its interface including any import, export parameters etc and for your convenience any standard documentation available. All this information and more can be viewed if you enter the function module name GET_BALANCE_RG1 into the relevant SAP transaction such as SE37 or SE80.
CALL FUNCTION 'GET_BALANCE_RG1' "Maintains RG1 opening/closing balances EXPORTING * i_datum = SY-DATUM " sy-datum i_exgrp = " j_1ipart1-exgrp * i_werks = " t001w-werks i_matnr = " mara-matnr i_form = " j_2irg1bal-form i_func = " j_2icomm-c1 * i_rg1bal = " j_2irg1bal IMPORTING e_rg1bal = " j_2irg1bal RG1 Balance record EXCEPTIONS NOT_FOUND = 1 " Not found PARAMETER_ERROR = 2 " Parameter error ERROR_OCCURED = 3 " Unknown error occured . " GET_BALANCE_RG1