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

From: Rolf Turner <>
Date: Fri, 22 Apr 2011 09:39:03 +1200

On 22/04/11 07:08, Cliff Clive wrote:
> I've been reading some code from an example in a blog post (
> 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?

Install the "fortunes" (if you haven't already) and see:



             Rolf Turner mailing list PLEASE do read the posting guide and provide commented, minimal, self-contained, reproducible code. Received on Thu 21 Apr 2011 - 21:42:04 GMT

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