[R] dist - memory

[Laurent Gautier]

Pesl Thomas wrote:
> 
> Dear R friends,
> 
> Is there a formula for the amount of memory, that is needed by dist(), when
> you know the number of columns and rows? Or is there at least an
> approximation?

As stated in the help for 'dist', the distance per row is computed, and
only the lower triangle is stored in a single vector.

Counting 8 bytes per numerical value, the memory used should be close to
8*nrows*nrows/2, upon which one should add the attributes of a dist
object should added (you may want to neglect as the number of rows gets
bigger).



Laurent


-- 
Laurent Gautier			CBS, Building 208, DTU
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