因子和Inf/NaN

Question

我寫了一個函數，將R中的Inf/NaN值轉換爲NA。函數如下：

DSanity.replaceInfNan <- function(l) 
{ 
    l <- ifelse((is.infinite(l))|(is.nan(l)), NA, l); 
    return(l) 
} 

但是，當類（l）是一個因子時，此函數返回類integer的對象。任何解決方案獲得相同的類沒有明確檢查類因素？下面給出一個例子。

dput(m)  
structure(c(2L, 2L, 3L, 4L, 5L, 6L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 
    9L, 10L, 11L, 12L, 13L, 14L, 15L, 16L, 17L, 18L, 19L, 20L, 21L, 
    22L, 23L, 24L, 25L, 26L, 27L, 28L, 29L, 2L, 2L, 3L, 4L, 5L, 6L, 
    7L, 8L, 9L, 10L, 11L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 
    2L, 3L, 4L, 5L, 6L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 
    12L, 13L, 14L, 15L, 16L, 17L, 18L, 19L, 20L, 21L, 22L, 23L, 24L, 
    25L, 26L, 27L, 2L, 3L, 4L, 2L, 3L, 4L, 2L, 3L, 4L, 5L, 6L, 7L, 
    8L, 9L), .Label = c("1984", "1985", "1986", "1987", "1988", "1989", 
    "1990", "1991", "1992", "1993", "1994", "1995", "1996", "1997", 
    "1998", "1999", "2000", "2001", "2002", "2003", "2004", "2005", 
    "2006", "2007", "2008", "2009", "2010", "2011", "2012", "2013" 
    ), class = "factor") 

class(DSanity.replaceInfNan(m)) 
"integer" 

Answer 1

DSanity.replaceInfNan <- function(l) { 
    l[is.infinite(l) | is.nan(l)] <- NA 
    return(l) 
}