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#206 Interpreter code generation failed for function returning a Type ←	↑	→ #208 interpret(x::InputFor)=x is broken for functions and types

#207 certain limit failure

Edit detail for #207 certain limit failure revision 1 of 3

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Editor: Time: 2007/11/17 22:08:37 GMT-8
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changed:
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Consider the following two expressions:

\begin{axiom}
exa:=integrate(log(1/x)/x^a,x)
exb:=integrate(log(1/x)*x^b,x)
\end{axiom}
which are equivalent by setting $a=-b$.
However, the operation 'limit' doesn't like both equally well:
\begin{axiom}
limit(exa,x=0)
limit(exb,x=0)
\end{axiom}

Martin

Consider the following two expressions:

fricas

exa:=integrate(log(1/x)/x^a,x)

$\label{eq1}{{{\left(- a + 1 \right)}\ x \ {\log \left({1 \over x}\right)}}+ x}\over{{\left({{a}^{2}}-{2 \ a}+ 1 \right)}\ {{e}^{-{a \ {\log \left({1 \over x}\right)}}}}}$

(1)

Type: Union(Expression(Integer),...)

fricas

exb:=integrate(log(1/x)*x^b,x)

$\label{eq2}{{\left({{\left(b + 1 \right)}\ x \ {\log \left({1 \over x}\right)}}+ x \right)}\ {{e}^{-{b \ {\log \left({1 \over x}\right)}}}}}\over{{{b}^{2}}+{2 \ b}+ 1}$

(2)

Type: Union(Expression(Integer),...)

which are equivalent by setting . However, the operation limit doesn't like both equally well:

fricas

limit(exa,x=0)

   >> Error detected within library code:
   can not determine sign

Martin