Re: proper way to manipulate lists?
- To: mathgroup at smc.vnet.net
- Subject: [mg40218] Re: [mg40182] proper way to manipulate lists?
- From: Hugh Walker <hwalker at gvtc.com>
- Date: Wed, 26 Mar 2003 02:42:23 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
On Tuesday, March 25, 2003, at 02:04 AM, Nathan Moore wrote:
>
> I'm sure this is a one-liner, but it has stumped me for years. Suppose
> I'm working with a 2-d array of data,
> data = {{x1,y1},{x2,y2}...{xN,yN}};
> and I want to transform the data according to,
> data2 = {{x1*a,y1*b},{x2*a,y2*b}...{xN*a,yN*b}};
> The only way I know to do this is to move the data to excel,
> performing the transform and then move the data back to Mathematica.
> This
> is crazy - there must be a better way - is there? Please tell me there
> is!
Let data be a given 2-dimensional list, and vec = {a,b}. Then the
operation
(vec(data//Transpose))//Transpose
will give the desires result.
=========
Hugh Walker
Gnarly Oaks