Re: put some elements to zero
- To: mathgroup at smc.vnet.net
- Subject: [mg101470] Re: [mg101438] put some elements to zero
- From: Tomas Garza <tgarza10 at msn.com>
- Date: Wed, 8 Jul 2009 07:10:11 -0400 (EDT)
- References: <200907071146.HAA27467@smc.vnet.net>
You might try
mat/.{x_=2C y_}->{x=2CIf[y<x0=2C 0=2C y]}
Not too bad=2C is it?
mat=Table[{RandomInteger[{0=2C99}]=2CRandomInteger[{0=2C99}]}=2C{100000}]=
=3B
AbsoluteTiming[mat/.{x_=2C y_}->{x=2C If[y<25=2C 0=2C y]}=3B]
{0.2652000=2CNull}
Tomas Garza
> Dear All=2C
> I have a matrix with only two columns and many rows. For instance
> {xi=2Cyi}.
> For those xi<x0=2C I would like to set yi=0.
> I can only think of a very inefficient loop...
>
> thanks
> -Luigi-
>
- References:
- put some elements to zero
- From: Luigi B <L.Balzano@gmail.com>
- put some elements to zero