Re: what's wrong?!!
- To: mathgroup at smc.vnet.net
- Subject: [mg115835] Re: what's wrong?!!
- From: Peter Pein <petsie at dordos.net>
- Date: Sat, 22 Jan 2011 03:22:01 -0500 (EST)
- References: <ih16b7$jiq$1@smc.vnet.net> <ih3rd0$bga$1@smc.vnet.net> <ihbjk9$d9n$1@smc.vnet.net>
On 21.01.2011 10:28, olfa wrote:
>
> still have problem with Cases for another example:
>
> Cases[A[l1] == A[l2]&& i + B[l2] == iP + B[l1], A | B, {0, Infinity}]
>
> returns {} why?!
>
Hi,
A and B are heads of expressions and therefore match _A|_B
In[1]:= Cases[
A[l1] == A[l2] && i + B[l2] == iP + B[l1], _A | _B, {0, Infinity}]
Out[1]= {A[l1], A[l2], B[l2], B[l1]}
if you want the heads only append "[[All, 0]]" to the above line to get
In[2]:= %[[All, 0]]
Out[2]= {A, A, B, B}
Cheers,
Peter