[R-SIG-Mac]A mac/win difference in R1.4.0

[Peter Macdonald]

Can anyone give me insight on this or suggest a better way? Thanks!

On the Mac I can write

    invmat <- try(solve(hessian/2))
    if (class(invmat) == "try-error")
        invmat <- matrix(NA, nrow = nrow(hessian), ncol = ncol(hessian))

But in Windows I have to add a test for null class or I get a fatal error
at the == when class is null

    invmat <- try(solve(hessian/2))
    if (!is.null(class(invmat)))
        if (class(invmat) == "try-error")
            invmat <- matrix(NA, nrow = nrow(hessian), ncol =
ncol(hessian))


*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
 Peter D.M. Macdonald, D.Phil.      McMaster University
 Professor of Math & Statistics     Hamilton, Ontario, Canada L8S 4K1
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