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 ```1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 ``` `````` \$LastChangedDate: 2008-07-11 10:31:18 +0200 (ven., 11 juil. 2008) \$ roots roots of polynomials Calling Sequence [x]=roots(p) [x]=roots(p,'e') Arguments p polynomial with real or complex coefficients or vector of the polynomial coefficients in decreasing degree order (Matlab compatibility). Description x=roots(p) returns in the complex vector x the roots of the polynomial p. For real polynomials of degree <=100 the fast RPOLY algorithm (based on Jenkins-Traub method) is used. In the other cases the roots are computed as the eigenvalues of the associated companion matrix. Use x=roots(p,'e') to force this algorithm in any cases. Examples See Also poly spec companion Authors Serge Steer (INRIA) References The RPOLY algorithm is described in "Algorithm 493: Zeros of a Real Polynomial", ACM TOMS Volume 1, Issue 2 (June 1975), pp. 178-189 Jenkins, M. A. and Traub, J. F. (1970), A Three-Stage Algorithm for Real Polynomials Using Quadratic Iteration, SIAM J. Numer. Anal., 7(1970), 545-566. Jenkins, M. A. and Traub, J. F. (1970), Principles for Testing Polynomial Zerofinding Programs. ACM TOMS 1, 1 (March 1975), pp. 26-34 Used Functions The rpoly.f source codes can be found in the directory SCI/modules/polynomials/src/fortran of a Scilab source distribution. In the case where the companion matrix is used, the eigenvalue computation is perfomed using DGEEV and ZGEEV LAPACK codes. ``````