[R] Amount of memory occupied by data type
Michael.Folkes at dfo-mpo.gc.ca
Wed Mar 14 17:25:47 CET 2012
Thanks David for the details and pointer to bitops functions. Buried a
bit deep that was.
I like to think the memory constraints of win xp keeps my code lean and
efficient. RAM is like a suburban garage, the bigger it is, the more
useless junk people stuff in there.
From: David Winsemius [mailto:dwinsemius at comcast.net]
Sent: March 13, 2012 5:25 PM
To: Folkes, Michael
Cc: r-help at r-project.org
Subject: Re: [R] Amount of memory occupied by data type
On Mar 13, 2012, at 7:02 PM, Folkes, Michael wrote:
> Hello all,
> I was under the (false?) assumption that an object that is class
> logical, would take up less memory than an object with class integer.
> Below am I correctly showing this is not the case?
> This was an attempt to reduce memory usage.
I think there is a package that will do bitwise operations. Yep... all
we needed to do is look:
> I'm dealing with two large
> arrays (could be integers). Their contents are the exact same, but
> one has NA's in random locations. I thought instead of having the
> second array as an integer, it could be logical and the TRUE vs FALSE
> could be used to update data in the first array. (but even this idea
> may be weak if I just end up with a third temporary array...)
You probably would since any assignment is going to create a copy. And
even having a bitwise logical option wouldn't necessarily help since the
indexing would be of necessity either integer or logical (both 8 bit
> I'm running win xp sp3, "R version 2.14.1 (2011-12-22)".
31-bit addressing constraints as well? (That's so last decade.) You
aren't making life easy for yourself are you.
David Winsemius, MD
West Hartford, CT
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