Matlab daily Practice Poly Function _matlab Learning

Poly to find the characteristic polynomial of a matrix

>> a=[0 1 0;-4 4 0;-2 1 2]

A =

0 1 0
-4 4 0
-2 1 2

>> Poly (A)

Ans =

1-6 12-8

>> B=sym (A)

B =

[0, 1, 0]
[-4, 4, 0]
[-2, 1, 2]

>> Poly (B)

Ans =

X^3-6*x^2 + 12*x-8

POLY Convert roots to polynomial.
    POLY (a), when a was an n by n matrix, being a row vector with
    n+1 Elementswhich Are the coefficients of the
   characteristic polynomial, DET (Lambda*eye (SIZE (a))-A).
 
    POLY (v), when v are a vector, is a vector whose elements are
    thecoefficients of The polynomial whose roots are the
    elements OfV. For vectors, ROOTS and POLY are inverse
    functions Ofeach, up to ordering, scaling, and
&N bsp;   Roundofferror.
 
   roots (POLY (1:20)) generates Wilkinson ' s famous example.
 
  & nbsp Classsupport for inputs a,v:
      float:double, single
 
     Alsoroots, conv, residue, polyval.

Overloaded methods:
Sym/poly

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