R：运算符重载和Zoo对象中的Ops.zoo

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./

ops.R

Ops.zoo <- function (e1, e2) 

{
    e <- if (missing(e2)) {
        NextMethod(.Generic)
    }
    else if (any(nchar(.Method) == 0)) {
        NextMethod(.Generic)
    }
    else {
    merge(e1, e2, all = FALSE, retclass = NULL)
        NextMethod(.Generic)
    }
    out <- if (is.null(attr(e, \"index\"))) 
    zoo(e, index(e1), attr(e1, \"frequency\"))
    else
    e
    # the next statement is a workaround for a bu g in R
    structure(out, class = class(out))
}

 e1 <- zoo(rnorm(5), as.Date(paste(2003, 02, c(1, 3, 7, 9, 14), sep = \"-\")))
 e2 <- e1
 test <- merge(e1, e2, all = FALSE, retclass = NULL)

NULL