ff (version 2.2-14)

nrowAssign: Assigning the number of rows or columns

Description

Function nrow<- assigns dim with a new number of rows. Function ncol<- assigns dim with a new number of columns.

Usage

nrow(x) <- value
ncol(x) <- value

Arguments

x

a object that has dim AND can be assigned ONE new dimension

value

the new size of the assigned dimension

Value

The object with a modified dimension

Details

Currently only asssigning new rows to ffdf is supported. The new ffdf rows are not initialized (usually become zero). NOTE that

See Also

ffdf, dim.ffdf

Examples

# NOT RUN {
  a <- as.ff(1:26)
  b <- as.ff(factor(letters)) # vmode="integer"
  c <- as.ff(factor(letters), vmode="ubyte")
  df <- ffdf(a,b,c)
  nrow(df) <- 2*26
  df
  message("NOTE that the new rows have silently the first level 'a' for UNSIGNED vmodes")
  message("NOTE that the new rows have an illegal factor level <0> for SIGNED vmodes")
  message("It is your responsibility to put meaningful content here")
  message("As an example we replace the illegal zeros by NA")
  df$b[27:52] <- NA
  df

  rm(a,b,c,df); gc()
# }