To work with rows rather than columns, transpose
the matrix, and then:

Method 0: the columns are linearly independent if
the matrix is invertible.

lii=: 1:@%. ::0:

Method 1: the columns are linearly independent
if the determinant is non-zero:

lid=: 0: ~: [: -/ .* (|: +/ .* ])^:(>/@$)

Moreover, use rational numbers depending on
how confident you are about the precision of 
the values. e.g.

   lid % >: +/~ i.30  NB. ye olde Hilbert matrix
0
   lid % >: +/~ i.30x
1



----- Original Message -----
From: Raul Miller <[EMAIL PROTECTED]>
Date: Friday, September 7, 2007 6:50
Subject: [Jgeneral] linear independence?
To: General forum <[email protected]>

> What's a good way to determine whether the rows of a
> matrix are linearly independent?
> 
> I was thinking that %:@%:^:_ would provide meaningful
> information, but:
> 
>    %:@%:^:_ p:i.3 3
> 1 1 1
> 1 1 1
> 1 1 1
> 
> I do not believe that the rows of p:i.3 3 linearly
> dependent on each other.  Am I wrong?  If so,
> how can this be demonstrated?
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