[R] What does the "<<-" operator mean?

[Roy Mendelssohn]

?assignOps

-Roy M.
On Apr 21, 2011, at 12:08 PM, Cliff Clive wrote:

> I've been reading some code from an example in a blog post (
> http://www.maxdama.com/ here ) and I came across an operator that I hadn't
> seen before.  The author used a <<- operator to update a variable, like so:
> 
> ecov_xy <<- ecov_xy+decay*(x[t]*y[t]-ecov_xy)
> 
> At first I thought it was a mistake and tried replacing it with the usual <-
> assignment operator, but I didn't get the same results.  So what does the
> double arrow <<- operator do?
> 
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Roy Mendelssohn
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NOAA/NMFS
Environmental Research Division
Southwest Fisheries Science Center
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