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2.25.15  Sturm sequences and number of sign changes of P on ]a; b] : sturm

sturm takes two or four arguments : P a polynomial expression or P/Q a rational fraction and a variable name or P a polynomial expression, a variable name and two real or complex numbers a and b.

If sturm takes two arguments, sturm returns the list of the Sturm sequences and multiplicities of the square-free factors of P (or P/Q) (in this case sturm behaves like sturmseq).

If sturm takes four arguments, it behaves like sturmab :

Input :

sturm(2*x^3+2,x)

Output :

[2,[[1,0,0,1],[3,0,0],-9],1]

Input :

sturm((2*x^3+2)/(x+2),x)

Output :

[2,[[1,0,0,1],[3,0,0],-9],1,[[1,2],1]]

Input :

sturm(x^2*(x^3+2),x,-2,0)

Output :

1

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