Roger Hui wrote:
> Have you tried   f=: f,a  ?  It should be in-place.

Thanks, Roger, you're right!  Either assembling the array in memory and
then writing it, or assembling it in a jmf file give comparable (non
quadratic) timings.

I think I was (a) impatient and (b) misled by the jmf lab:

"You can add a new item to an array:   name=: name,new

Eventually this phrase will be recognized and done in-place. But currently
it creates a temporary array which is then assigned to the name. This is
not good if name is a very large mapped file."

This is followed by an explanation of additem.

Since eventually is now, perhaps the lab could be updated.

Best wishes,

John



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