write.table               package:base               R Documentation

Data Output

Description:

     `write.table' prints its required argument `x' (after converting
     it to a data frame if it is not one already) to `file'.  The
     entries in each line (row) are separated by the value of `sep'.

Usage:

     write.table(x, file = "", append = FALSE, quote = TRUE, sep = " ",
                 eol = "\n", na = "NA", dec = ".", row.names = TRUE,
                 col.names = TRUE, qmethod = c("escape", "double"))

Arguments:

       x: the object to be written, typically a data frame.  If not, it
          is attempted to coerce `x' to a data frame.

    file: either a character string naming a file or a connection. `""'
          indicates output to the console.

  append: logical.  If `TRUE', the output is appended to the file.  If
          `FALSE', any existing file of the name is destroyed.

   quote: a logical or a numeric vector.  If `TRUE', any character or
          factor columns will be surrounded by double quotes.  If a
          numeric vector, its elements are taken as the indices of the
          variable (columns) to quote.  In both cases, row and columns
          names are quoted if they are written, but not if `quote is
          FALSE'.

     sep: the field separator string.  Values within each row of `x'
          are separated by this string.

     eol: the character(s) to print at the end of each line (row).

      na: the string to use for missing values in the data.

     dec: the string to use for decimal points.

row.names: either a logical value indicating whether the row names of
          `x' are to be written along with `x', or a character vector
          of row names to be written.

col.names: either a logical value indicating whether the column names
          of `x' are to be written along with `x', or a character
          vector of column names to be written.

 qmethod: a character string specifying how to deal with embedded
          double quote characters when quoting strings.  Must be one of
          `"escape"' (default), in which case the quote character is
          escaped in C style by a backslash, or `"double"', in which
          case it is doubled.  You can specify just the initial letter.

Details:

     Normally there is no column name for a column of row names.  If
     `col.names=NA' a blank column name is added.  This can be used to
     write CSV files for input to spreadsheets.

     `write.table' can be slow for data frames with large numbers
     (hundreds or more) of columns: this is inevitable as each column
     could be of a different class and so must be handled separately.
     Function `write.matrix' in package `MASS' may be much more
     efficient if `x' is a matrix or can be represented in a numeric
     matrix.

See Also:

     The `R Data Import/Export' manual.

     `read.table', `write'.

     `write.matrix'.

Examples:

     ## To write a CSV file for input to Excel one might use
     write.table(x, file = "foo.csv", sep = ",", col.names = NA)
     ## and to read this file back into R one needs
     read.table("file.csv", header = TRUE, sep = ",", row.names=1)

