[R] error message from regsubsets

[Rajarshi Guha]

Hi, I'm using regsubsets and it works fine when nvmax = 4. However when
I go for any value above 4, I get the error:

Warning message:
XHAUST returned error code -999 in: leaps.exhaustive(a, really.big =
really.big)

I'm calling regsubsets as:

lp <- regsubsets(x,y,nbest=1,nvmax=5,intercept=T,really.big=T,
method="exhaustive")

x is a data.frame with 40 variables and 277 observations (in the rows)
and y is a vector of length 277. The manual mentions that really.big
should be TRUE when there are more than 50 variables. But even if when I
set it to FALSE in the above command it still fails with the error
mesage.
Thanks

Could anybody explain what this error means?
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Rajarshi Guha <rxg218 at psu.edu> <http://jijo.cjb.net>
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