Subject: Fwd: bug report, or am I doing something wrong?
From: Robert Dodier
Date: Tue, 31 Jan 2006 08:44:57 -0700
Hello all -- a message from Luke Sharkey, which was intended for the mailing
list.
A quick look suggests the results below stem from Maxima's
choice of branches for multi-valued functions.
Robert Dodier
---------- Forwarded message ----------
From: Luke Sharkey <99LSharkey@ormskirk.lancs.sch.uk >
Date: Jan 31, 2006 7:59 AM
Subject: bug report, or am I doing something wrong?
To: Robert Dodier
*bug 1: *
* minus symbol lost along the way somewhere. What's gone wrong below?*
3.359 is a random number I picked for which I know this function has no real
solutions. Hence the negative number to a power of something nasty:
(%i7) subst(3.359, x, %);
(%i8) factor(%);
(%i10) if numer#false then numer:false else numer:true;
But after I factorise the imaginary number output of (%o7) resulting in
(%o8), then copy the output into the INPUT box and enter, it generates:
(%o14). Is this the result of a rounding error? It is now giving a
solution to an equation which is actually imaginary
(%i14) (0.94105328893399121*(-4802.4591729556541)^0.026385783124596718);
Even though in unfactorised form the below is generated, which doesn't have
a real solution, and if you try and solve (%o7) it will only output (%o7)
again.
Any ideas?
Thanks
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3.359 is a random number I picked for which I know this function has no real
solutions. Hence the negative number to a power of something nasty:
(%i7) subst(3.359, x, %);
(%i8) factor(%);
(%i10) if numer#false then numer:false else numer:true;
But after I factorise the imaginary number output of (%o7) resulting in
(%o8), then copy the output into the INPUT box and enter, it generates:
(%o14). Is this the result of a rounding error? It is now giving a
solution to an equation which is actually imaginary
(%i14) (0.94105328893399121*(-4802.4591729556541)^0.026385783124596718);
Even though in unfactorised form the below is generated, which doesn't have
a real solution, and if you try and solve (%o7) it will only output (%o7)
again.
Any ideas?
Thanks
***************************************************************************
This e-mail is confidential and privileged. If you are not the intended
recipient do not disclose, copy or distribute information in this e-mail
or take any action in reliance on its content.
***************************************************************************
***************************************************************************
This email has been checked for known viruses.
***************************************************************************