y=(exp(x)+log(abs(sin(x)^2-sin(x*x))))/(x-5*i)
A=[4,15,-45,10,6;56,0,17,-45,0]
A =
k=find(ch>='a'&ch<='z');
ch(k)=ch(k)-('a'-'A');
char(ch)
WELCOME TO BEIJING
length(k)
R=[1,2,3;4,5,6];
M=[11,12,13;14,15,16];
RM=R+i*M
a=[1,2,3;4,5,6];
b=[11,12,13,14;15,16,17,18];
c=fsetcomp(a,b)
例 2.2