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Edit detail for #262 Local variables in output revision 5 of 5

1 2 3 4 5
Editor: test1
Time: 2017/02/23 18:45:00 GMT+0
Note:

changed:
-In some cases Axiom's output contains temporary names such
-as '%x0' standing for subexpressions that are not properly
-substituted into the final result. For example:
In some cases FriCAS introduces special names such
as '%x0' standing for roots. For example:

changed:
-From kratt6 Thu Feb 2 09:50:56 -0600 2006
-From: kratt6
-Date: Thu, 02 Feb 2006 09:50:56 -0600
-Subject: not really temporary
-Message-ID: <20060202095056-0600@wiki.axiom-developer.org>
-
-These names are not really temporary:
That is OK and we can learn about defining equation like this:

changed:
-(However, I think they should be...)
-
-From kratt6 Thu Feb 2 09:55:41 -0600 2006
-From: kratt6
-Date: Thu, 02 Feb 2006 09:55:41 -0600
-Subject: 
-Message-ID: <20060202095541-0600@wiki.axiom-developer.org>
-
-Note that the expression (3) surfaces another bug in the solver: the variable 'x' should not appear in the defining polynomial of '%x0'...
-
-Martin
-
-From kratt6 Fri Dec 28 05:39:38 -0800 2007
-From: kratt6
-Date: Fri, 28 Dec 2007 05:39:38 -0800
-Subject: Maybe difficult to understand for newcomers, but correct
-Message-ID: <20071228053938-0800@axiom-wiki.newsynthesis.org>
-
-Category: Axiom Mathematics => Axiom User Interface 
-Status: open => closed 
-
-
-From kratt6 Fri Dec 28 05:46:58 -0800 2007
-From: kratt6
-Date: Fri, 28 Dec 2007 05:46:58 -0800
-Subject: 
-Message-ID: <20071228054658-0800@axiom-wiki.newsynthesis.org>
-
-Status: closed => rejected 
-
-
-From BillPage Fri Oct 16 12:09:46 -0700 2009
-From: Bill Page
-Date: Fri, 16 Oct 2009 12:09:46 -0700
-Subject: There's Something Wrong with this output, right?
-Message-ID: <20091016120946-0700@axiom-wiki.newsynthesis.org>
-
-Old example
-
-\begin{axiom}
-3*x*x+2*x+12*sin(12*x)
-integrate(%, x)
-zerosOf(%,x)
-\end{axiom}
-
However, in this case the expression (3) surfaces bug in the solver: the variable 'x' should not appear in the defining
polynomial of '%x0'.  In fact, since the equation is not a polynomial in 'x' 'zerosOf' should probably reject it.




Submitted by : (unknown) at: 2007-11-17T22:17:39-08:00 (14 years ago)
Name :
Axiom Version :
Category : Severity : Status :
Optional subject :  
Optional comment :

In some cases FriCAS introduces special names such as %x0 standing for roots. For example:

fricas
eq:=-cos(12*x)+x^2+x^3

\label{eq1}-{\cos \left({{12}\  x}\right)}+{{x}^{3}}+{{x}^{2}}(1)
Type: Expression(Integer)
fricas
zerosOf(eq,x)

\label{eq2}\begin{array}{@{}l}
\displaystyle
\left[ \%x 0, \:{{{\sqrt{-{3 \ {{\%x 0}^{2}}}-{2 \  \%x 0}+ 1}}- \%x 0 - 1}\over 2}, \: \right.
\
\
\displaystyle
\left.{{-{\sqrt{-{3 \ {{\%x 0}^{2}}}-{2 \  \%x 0}+ 1}}- \%x 0 - 1}\over 2}\right] 
(2)
Type: List(Expression(Integer))

That is OK and we can learn about defining equation like this:

fricas
definingPolynomial %x0

\label{eq3}-{\cos \left({{12}\  x}\right)}+{{\%x 0}^{3}}+{{\%x 0}^{2}}(3)
Type: Expression(Integer)

However, in this case the expression (3) surfaces bug in the solver: the variable x should not appear in the defining polynomial of %x0. In fact, since the equation is not a polynomial in x zerosOf should probably reject it.