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Topic: Rank of root
Replies: 2   Last Post: Dec 29, 2012 1:32 PM

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 Triet Posts: 3 Registered: 12/29/12
Re: Rank of root
Posted: Dec 29, 2012 1:32 PM

"Roger Stafford" wrote in message <kbnarq\$302\$1@newscl01ah.mathworks.com>...
> "Triet" wrote in message <kbm7qf\$bn2\$1@newscl01ah.mathworks.com>...
> > I know Matlab has "factor" to factor an equation, but is there any function or any way to do this in Matlab:
> > -Input: an equation ex: x^3 -8*x^2 + 20*x -16
> > -Output:
> > +the equation factored, ex: (x - 4)*(x - 2)^2
> > +Solve the equation, ex: x1=4; x2=2
> > +Most important: show the rank of each root (the power of each inner expression) , ex: root 1 = 4 has rank = 1; root 2 = 2 has rank = 2

> - - - - - - - - -
> Besides the symbolic 'factor' there is the numeric 'roots' function from which you can obtain the above information by comparing the polynomial's roots. For a polynomial with real coefficients a pair of roots which are complex conjugates of one another will give you a quadratic factor. Note that roots which are equal may suffer slightly differing round-off errors so your comparisons should have a tolerance for small differences.
>
> Roger Stafford

Thank you. That helped me very much.

Date Subject Author
12/29/12 Triet
12/29/12 Roger Stafford
12/29/12 Triet