Hello. I'm fairly new to Sage, so lets see if someone more experienced can help!
Say I have a function f(x) continuous in [a,b] and derivable in (a,b). How can I implement in Sage a function 'maximum(f,a,b)' that returns the maximum of f(x) in [a,b] (as a numerical approximation, not as an expression)?
Thanks you a lot!
find_maximum_on_interval?
sage: f = lambda x:-4*x^6/(x^4 + 1)^(3/2) + 6*x^2/sqrt(x^4 + 1)
sage: find_maximum_on_interval(f,0,2)
(2.8284271247461898, 1.0000000183339277)
Not sure when the change occurred, but in SageMath 9.0, find_maximum_on_interval has been replaced with find_local_maximum.
Bear in mind this is a numerical method.
What would be wrong with f.diff(x).solve(x) (or diff(f(x),x).solve(x)) ?
The thing that's wrong with what you propose @Emmanuel Charpentier is that it doesn't find the local maximum.
For example take y = 2*x + 3; find_local_maximum(y, 1, 4) will return (10.999999837732908, 3.9999999188664543) while y.diff(x).solve(x) returns []
Asked: 2012-04-15 15:37:12 +0100
Seen: 9,184 times
Last updated: Jan 30 '20
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