11 ztee 12 ztee 21 ztee 22 of the z matrix z_tee are expressed as the following equations 18 to 20 by using the above equations 7 to 9 ztee 11 z 1 z 3 rind u2014 1 rind u2014 3 j u03c9 lind u2014 1 lind u2014 3 18 ztee 22 z 2 z 3 rind u2014 2 rind u2014 3 j u03c9 lind u2014 2 lind u2014 3 19 next as indicated in the following equation 21 by subtracting the z matrix z_tee of the t type circuit part 5 from a z matrix z_dut of the whole circuit of fig2 a z matrix z_dut u2032 of the u03c0 type circuit part 6 is calculated step s 5 next the z matrix z_dut u2032 is converted to a y matrix y_dut u2032 step s 6 the following relations are derived by using a four terminal y matrix if the equations 22 and 23 are substituted for i 1 and i 2 of the above equations 1 and 2 the following equations 24 and 25 are obtained z 11 u00b7 y 11 z 12 u00b7 y 21 u2212 1 v 1 z 11 u00b7 y 12 z 12 u00b7 y 22 v 2 0 24 z 21 u00b7 y 11 z 22 u00b7 y 21 u2212 1 v 1 z 21.