Timeline for Find extreme values in a polynomial expression
Current License: CC BY-SA 3.0
5 events
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| Oct 16, 2014 at 13:57 | comment | added | Daniel Lichtblau | That 6th solution might be the branch above the one of interest? They do come kind of close as you go far in eaither direction. As for solution ordering, I think it will be by root branch number, with the two quartics (if I recall correctly) themselves selected in an unknown order. "Branch number" is actually a misnomer in that it really means "root order", but only gets resolved upon substituting actual values for the parameters. The branches can and do jump, as in the case of the one of interest (notice the cusp, where two algebraic function branches have crossed). | |
| Oct 16, 2014 at 9:34 | comment | added | MXJ |
Hi @DanielLichtblau, One comment: I find interesting and "unpredictable" the way in which Solve sorts its solutions. Usually to circumvent this I would use Sort[solns]... If I do so the branch of interest is #6 (the solutions are then obviously sorted in growing order of omega). But then executing FindMaximum[\[HBar] Sort[solns][[6]], {k, 10^6}] returns {11.6345, {k -> 1.1*10^7}}, which is obviously wrong! I wonder why that is and shall investigate this further.
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| Oct 16, 2014 at 9:28 | comment | added | MXJ | Hi @Daniel, thank you very much for this answer. It really looks like exactly what I needed :) | |
| Oct 16, 2014 at 9:27 | vote | accept | MXJ | ||
| Oct 15, 2014 at 22:41 | history | answered | Daniel Lichtblau | CC BY-SA 3.0 |