how much memory does one need...

to allocate 7.8 MB to a vector? (on R running on MacOS 8.6 with a 100MB
partition)

I get this error from a function which is trying to create a 1000x1000
matrix:

Error: cannot allocate vector of size 7812 Kb

the error occurs here:
dist <- as.single((t(pos)-pos)/n)

where pos is a matrix of integers, and n is the size of the first
dimension. It appears to first create a double with (t(pos)-pos)/n,
running out of memory before making it a single.

Several questions arise from this problem: 1) how do I determine how much
memory is free within the program?, 2) how do I determine how much memory
is being consumed by a given object?, 3) how do I force R to create a
matrix as a single rather than a double?

daver

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|David Richmond                It works on a          |      
+ Dept. of Sociology          complex scientific      + 
|Saint Mary's College          principle, known as    |  
+ Notre Dame, IN 46556               "pot luck."      +
|219-284-4517                    - The Doctor         |
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