[sage-support] Re: solution of a 4th degree equation is real despite containing I but causes trouble

Or range(abs(t))? Then if there is some numerical noise leading to a tiny imaginary part (your t might be evaluated to 2.573037896825689 - 4.365411232224172e-17*I for example), abs(t) won't care. On Wednesday, February 20, 2019 at 10:42:32 AM UTC-8, John H Palmieri wrote: > > How about

[sage-support] Re: solution of a 4th degree equation is real despite containing I but causes trouble

How about range(0, RR(t))? On Wednesday, February 20, 2019 at 10:11:14 AM UTC-8, Michael Beeson wrote: > > Oh, and range(0,n(t)) also crashes. > > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop

[sage-support] Re: solution of a 4th degree equation is real despite containing I but causes trouble

Oh, and range(0,n(t)) also crashes. -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send

[sage-support] solution of a 4th degree equation is real despite containing I but causes trouble

The solution of a cubic or quartic may require the use of complex numbers. (Indeed that's how the complex numbers were first discovered.) Below I exhibit a long expression for such a number that solve() found for me. It evaluates using n(t) to a real (decimal) number, and it passes " t in RR"

Re: [sage-support] Fwd: Sage Crash Report

On Wed, 20 Feb 2019 at 14:24, Douglas Webster wrote: > Thank you, Isuru, for the assistance, but I'm afraid it still isn't > working. The program is still crashing, but this time it seems to be the > elliptical curves module that is causing the problem. A copy of the crash > report is attached

Re: [sage-support] groebner basis algorithm: intended way of calling (out of other method)

On 2019-02-08 10:07, Daniel Krenn wrote: > Let I be an ideal. Then I might want to compute something involving > Groebner basis, e.g. computing I.variety(). > Now suppose one wants to select a particular algorithm for the > computation of the Groebner basis. Then (due to caching) I use something >

Re: [sage-support] Fwd: Sage Crash Report

Thank you, Isuru, for the assistance, but I'm afraid it still isn't working. The program is still crashing, but this time it seems to be the elliptical curves module that is causing the problem. A copy of the crash report is attached but I think I will reinstall the binary version of sage until

[sage-support] Re: trig simplify disappointed me

Well... Sage does not, indeed, "automagically" apply all possible trig identities . But perusing them allow to select (with a tiny grain of salt) the right one: sage: tan(1/2*arctan(12/5)).subs(tan(w0/2)==sin(w0)/(1+cos(w0))) 2/3 HTH,

[sage-support] trig simplify disappointed me

sage: t tan(1/2*arctan(12/5)) sage: t.trig_simplify() sin(1/2*arctan(12/5))/cos(1/2*arctan(12/5)) sage: n(t) 0.667 But trig_simplify couldn't get 2/3. Maybe there is a fancier command that will do it? -- You received this message because you are subscribed to the

[sage-support] Re: solve() behavior

after solving an equation (or not) for x, I can check if the answer still contains x by ans.has(x). That should weed out any non-explicit solutions. But still: am I guaranteed for any class of equations, e.g. polynomial equations of degree <= 4, that if solve produces an empty list there