486
Practical MATLAB
® Applications for Engineers
F2 _ z =
z/a/(z/a-1)
>> pretty(F2 _ z)
z
---------a (z/a - 1)
>> f3 _ n =1^n*cos(a*n);
% part (c)
>> F3 _ z = ztrans(f3 _ n)
F3 _ z =
(z-cos(a))*z/(z^2-2*z*cos(a)+1)
>> pretty(F3 _ z)
(z - cos(a)) z
------------------2
z - 2 z cos(a) + 1
>> f4 _ n =1^n*sin(a*n);
% part(d)
>> F4 _ z = ztrans(f4 _ n)
F4 _ z =
z*sin(a)/(z^2-2*z*cos(a)+1)
>> pretty(F4 _ z)
z sin(a)
------------------2
z - 2 z cos(a) + 1
>> f5 _ n = b^n*sin(a*n);
% part(e)
>> F5 _ z =ztrans(f5 _ n)
F5 _ z =
z/b*sin(a)/(z^2/b^2-2*z/b*cos(a)+1)
>> pretty(F5 _ z)
z sin(a)
---------------------------/
2
\
│ z
z cos(a)
│
b │---- - 2 -------- + 1 │
│
2
b
│
\ b
/
R.5.78 Write the script fi le sym_z_plots that returns the plots of F1_z, F2_z, F3_z, and F4_z
versus z, defi ned in R.5.77 for a = 0.5
CRC_47760_CH005.indd 486
CRC_47760_CH005.indd 486
7/23/2008 1:47:25 PM
7/23/2008 1:47:25 PM