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[Octave-bug-tracker] [bug #56062] Strange result solving a simple proble
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From: |
Rik |
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Subject: |
[Octave-bug-tracker] [bug #56062] Strange result solving a simple problem |
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Date: |
Tue, 2 Apr 2019 16:41:17 -0400 (EDT) |
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User-agent: |
Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko |
Update of bug #56062 (project octave):
Category: Octave Function => Interpreter
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Follow-up Comment #2:
This is just math, nothing particularly strange.
If you raise a negative number to the 1/3rd power you are going to get a
complex result. Break it up in to individual calculations
octave:4> sqrt (21)
ans = 4.5826
octave:5> 3 * ans
ans = 13.748
octave:6> 8 - ans
ans = -5.7477
octave:7> ans^(1/3)
ans = 0.89564 + 1.55130i
On the other hand, in the second example there is a call to abs(), or absolute
value, which removes the minus sign.
octave:11> abs(8-3*sqrt(21))
ans = 5.7477
octave:12> ans^(1/3)
ans = 1.7913
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Reply to this item at:
<https://savannah.gnu.org/bugs/?56062>
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