chap4 .....\chap4_1.m .....\chap4_10.m .....\chap4_2.m .....\CHAP4_3.M .....\CHAP4_4.M .....\chap4_5.m .....\chap4_6.m .....\chap4_7.m .....\chap4_8.mdl .....\chap4_8m1.m .....\chap4_8m2.m .....\chap4_9.m .....\chap4_9eq.m