Re: Sum of terms --> list
- To: mathgroup at smc.vnet.net
- Subject: [mg110601] Re: Sum of terms --> list
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Sun, 27 Jun 2010 04:56:51 -0400 (EDT)
On 6/26/10 at 3:09 AM, dxcqp2000 at gmail.com (uno) wrote:
>I have an expression that is a sum of terms, like a+b+c and I want to
>convert it to a list, with as many elements as the number of terms in
>the sum of terms, and with each element being each of the terms, like
>{a,b,c}
The way to do this is to use Apply. That is
In[1]:= sum = a + b + c;
List @@ sum
Out[2]= {a,b,c}
Mathematica stores sum as:
In[3]:= FullForm[sum]
Out[3]//FullForm= Plus[a,b,c]
The @@ (shorthand for Apply) replaces the head Plus in sum with
the head List yielding the desired result. And since this works
on any expression, your product can be converted to a list in
the same manner
>Also, the same to go from a product of terms like a*b*c to a list like
>{a,b,c}
In[4]:= prod = a b c;
List @@ prod
Out[5]= {a,b,c}