From: Joel VanderWerf <vjoel@...>
Date: 2008-10-17T04:38:28+09:00
Subject: Re: NArray help

Joe Lovick wrote:
> Hi,
> 
>  Could someone please tell me how the syntax works for the narray, max
> and min methods.
> 
>  if i use @values.max i get the max of the entire array, after reading
> the narray documentation http://narray.rubyforge.org/SPEC.en it looks
> like i can get the max of a particular dimension at an orthogonal index,
> however, i am at a loss to work out how this should be specified
> syntatically.
> 
>  to put it another way, i have a 2D array, and i would like to find the
> max and the min, of each of the columns 1..n.

This maybe?

irb(main):006:0> a = NArray[ [1,2,3], [4,5,6] ]
=> NArray.int(3,2):
[ [ 1, 2, 3 ],
   [ 4, 5, 6 ] ]
irb(main):007:0> a.max(0)
=> NArray.int(2):
[ 3, 6 ]
irb(main):008:0> a.max(1)
=> NArray.int(3):
[ 4, 5, 6 ]

So I guess 0 means "max over each row", and 1 means "max over each column".

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407