Series[] nested (bug?)
- To: mathgroup at smc.vnet.net
- Subject: [mg71196] Series[] nested (bug?)
- From: "ben" <benjamin.friedrich at gmail.com>
- Date: Fri, 10 Nov 2006 06:37:55 -0500 (EST)
Dear group,
I experienced a strange behaviour of
Series[ Series[] ]-constructs:
The expansion may contain higher-order terms which shouldn't be there.
Switching to
Series[ Series[] //Normal ]
fixes the problem.
Can anyone explain this behaviour?
Ben
Heres an example
In[208]:=
truncate[exp_]:=Series[exp,{\[Epsilon],0,1}]
In[209]:=
truncate[\[Epsilon] truncate[1+\[Epsilon]]]
Out[209]=
\!\(\*
InterpretationBox[
RowBox[{"\[Epsilon]", "+", \(\[Epsilon]\^2\), "+",
InterpretationBox[\(O[\[Epsilon]]\^3\),
SeriesData[ \[Epsilon], 0, {}, 1, 3, 1],
Editable->False]}],
SeriesData[ \[Epsilon], 0, {1, 1}, 1, 3, 1],
Editable->False]\)
In[206]:=
truncate[exp_]:=Series[exp//Normal,{\[Epsilon],0,1}]
In[207]:=
truncate[\[Epsilon] truncate[1+\[Epsilon]]]