Re: [Rd] modifying large R objects in place

From: Petr Savicky <>
Date: Thu, 27 Sep 2007 15:51:51 +0200

In my previous email, I sent the example:
> a <- matrix(as.integer(1),nrow=14100,ncol=14100) # 774m
> a[1,1] <- 0 # 3.0g
> gc() # 1.5g

This is misleading. The correct version is

   a <- matrix(as.integer(1),nrow=14100,ncol=14100) # 774m    a[1,1] <- as.integer(0) # 1.5g
   gc() # 774m

So, the object duplicates, but nothing more.

The main part of my previous email (question concerning a possible bug in the behavior of nrow(a) and ncol(a)) remains open.

Petr Savicky. mailing list Received on Thu 27 Sep 2007 - 13:55:10 GMT

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