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Re: Rank of root
Posted:
Dec 29, 2012 12:56 PM


"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 roundoff errors so your comparisons should have a tolerance for small differences.
Roger Stafford



