Biomedical Engineering Reference
In-Depth Information
>>
conv(z, w)
resulting in
s
s
¼
¼
1.0e
012
*
Columns 1 through 4
0.00000000002700
þ
0.00000005670000
0.00004464000000
0.01561600000000
Column 5
2.04800000000000
3
multiplied by the right-side numerator term
is (27x
4
),
The left-side denominator term 27
x
x
written in MATLAB as
>>
q
¼
[270000]
giving
q
¼
270000
Next, we subtract the two polynomials, using the MATLAB command
>>
t
¼
s
q
resulting in
t
¼
1.0e
012
*
Columns 1 through 4
0
þ
0.00000005670000
0.00004464000000
0.01561600000000
Column 5
2.04800000000000
The polynomial evaluated by the previous steps can be written as
10
4
3
10
7
2
10
10
10
12
0
The final step in the problem is to evaluate the roots of the resulting polynomial:
5.67
x
þ
4.464
x
þ
1.5616
x
þ
2.048
¼
>>
v
¼
roots(t)
which yields
v
¼
1.0e
002
*
2.62504409150663
þ
þ
2.62297313283571i
2.62504409150663
2.62297313283571i
2.62292769000261
Two of the roots are complex and are eliminated because they fall outside the problem con-
straints, giving a solution of
x
¼
262
:
3
Table A.2 summarizes some MATLAB commands used for evaluating polynomials.