ConstantCoefficient of polynomial
- Subject: [mg3368] ConstantCoefficient of polynomial
- From: wagner at bullwinkle.cs.Colorado.EDU (Dave Wagner)
- Date: 2 Mar 1996 14:43:53 -0600
- Approved: usenet@wri.com
- Distribution: local
- Newsgroups: wri.mathgroup
- Organization: University of Colorado, Boulder
- Sender: daemon at wri.com
Whoops, a following to my previous post about finding the constant
coefficient of a polynomial. I proposed:
In[1]:=
ConstantCoefficient[poly_Plus] := Select[poly, NumberQ[N[#]]&]
In[3]:=
ConstantCoefficient[E^2 + Pi + Sqrt[7]x + Sqrt[5]]
Out[3]=
2
Sqrt[5] + E + Pi
which works fine as long as there IS a constant coefficient.
If not, it does not evaluate (by design):
In[8]:=
ConstantCoefficient[Sqrt[7]x]
Out[8]=
ConstantCoefficient[Sqrt[7] x]
This is easily handled by specifying a "catch-all" case that returns 0:
In[9]:=
ConstantCoefficient[_] := 0
In[10]:=
ConstantCoefficient[Sqrt[7]x]
Out[10]=
0
Dave Wagner
Principia Consulting
(303) 786-8371
dbwagner at princon.com
http://www.princon.com/princon