http://www.mapleprimes.com/questions/41349-Positive-Root-Of-Polynomial en-us 2026 Maplesoft, A Division of Waterloo Maple Inc. Maplesoft Document System Fri, 12 Jun 2026 13:32:31 GMT Fri, 12 Jun 2026 13:32:31 GMT The latest answers and comments added to the Question, positive root of polynomial http://www.mapleprimes.com/images/mapleprimeswhite.jpg http://www.mapleprimes.com/questions/41349-Positive-Root-Of-Polynomial http://www.mapleprimes.com/questions/41349-Positive-Root-Of-Polynomial?ref=Feed:MaplePrimes:positive root of polynomial:Comments#answer77000 From a previous posting: <a href="http://beta.mapleprimes.com/forum/how-do-i-take-only-positive-root-from-solve-polynomial-x">http://beta.mapleprimes.com/forum/how-do-i-take-only-positive-root-from-solve-polynomial-x <em>Regards, Georgios Kokovidis Dräger Medical</em> From a previous posting: <a href="http://beta.mapleprimes.com/forum/how-do-i-take-only-positive-root-from-solve-polynomial-x">http://beta.mapleprimes.com/forum/how-do-i-take-only-positive-root-from-solve-polynomial-x <em>Regards, Georgios Kokovidis Dräger Medical</em> 77000 Tue, 22 May 2007 17:18:11 Z gkokovidis gkokovidis http://www.mapleprimes.com/questions/41349-Positive-Root-Of-Polynomial?ref=Feed:MaplePrimes:positive root of polynomial:Comments#answer76994 If you wish to apply some theory yourself then you could first try a web search for Descarte's rules of signs, or the Sturm theorem. In Maple 11, for a univariate polynomial with rational real coefficients the new command RootFinding[Isolate] can bracket the roots within rational intervals. Judging by the Description in its Maple help-page the underlying methods that it uses do not work internally with floating-point numbers, and do not miss roots due to round-off or related issues. You did not mention whether the coefficients are rational or floating-point. If any of the coefficients are floating-point real number approximations then you could use fsolve rather than RootFinding[Isolate] directly. acer If you wish to apply some theory yourself then you could first try a web search for Descarte's rules of signs, or the Sturm theorem. In Maple 11, for a univariate polynomial with rational real coefficients the new command RootFinding[Isolate] can bracket the roots within rational intervals. Judging by the Description in its Maple help-page the underlying methods that it uses do not work internally with floating-point numbers, and do not miss roots due to round-off or related issues. You did not mention whether the coefficients are rational or floating-point. If any of the coefficients are floating-point real number approximations then you could use fsolve rather than RootFinding[Isolate] directly. acer 76994 Tue, 22 May 2007 19:22:26 Z acer acer http://www.mapleprimes.com/questions/41349-Positive-Root-Of-Polynomial?ref=Feed:MaplePrimes:positive root of polynomial:Comments#comment85526 Thanks for answers. fsolve is not the best solution in my case. My polynomials have rational coefficients and their roots are in the interval [0, 1.5]. So I will try Isolate and Next. I plan to tell about my experiences in the near future. Sandor Thanks for answers. fsolve is not the best solution in my case. My polynomials have rational coefficients and their roots are in the interval [0, 1.5]. So I will try Isolate and Next. I plan to tell about my experiences in the near future. Sandor 85526 Tue, 22 May 2007 21:24:28 Z SandorSzabo SandorSzabo http://www.mapleprimes.com/questions/41349-Positive-Root-Of-Polynomial?ref=Feed:MaplePrimes:positive root of polynomial:Comments#comment91432 The Next is very efficient. My proc is very fast. Thanks again. Sandor The Next is very efficient. My proc is very fast. Thanks again. Sandor 91432 Tue, 22 May 2007 23:34:47 Z SandorSzabo SandorSzabo