Re: Adding elements of a matrix
- To: mathgroup at smc.vnet.net
- Subject: [mg40738] Re: Adding elements of a matrix
- From: "Dana DeLouis" <delouis at bellsouth.net>
- Date: Tue, 15 Apr 2003 04:00:27 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Just another option...
w = Array[v, {3, 5}]; MatrixForm[w]
Dimensions[w]
{3, 5}
With[
{d = Dimensions[w]},
Plus @@ Flatten[Table[w[[i,j]], {i, d[[1]]}, {j, i + 1, d[[2]]}]]
]
= = = = = = = = = = =
> for example i have a matrix m[[i,j]] and i want to add every term
where
> i<j (this is to avoiding adding twice the same number)
--
Dana DeLouis
Windows XP
$VersionNumber -> 4.2
= = = = = = = = = = = = = = = = =
"Rebeca Choy" <rchoy at ula.ve> wrote in message
news:b738oh$o7l$1 at smc.vnet.net...
> Hi,
>
> How can I add in Mathematica every element of a matrix without adding
> twice the mixed terms?
>
> for example i have a matrix m[[i,j]] and i want to add every term
where
> i<j (this is to avoiding adding twice the same number)
>
> Can I do it with Sum?
>
> Rebeca Choy