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RSurvey (version 0.8-3)

ImportText: Import Data from Text File

Description

A GUI for reading table formatted data from a text file.

Usage

ImportText(parent = NULL)

Arguments

parent
tkwin; the GUI parent window.

Value

Sets the following components in Data:
data.raw
data.frame; the imported (or raw) data table.
cols
list; length equal to the current number of data variables. Each component in cols is linked to a specific variable, see ManageVariables.
comment
character; a vector of comment strings.
import
list; saved GUI options.
Components of import include:
source
character; a vector of length 2 that includes the pathname of the text file and access date.
fmts
logical; indicates whether the file contains the conversion specification format strings of the variables.
cols
logical; indicates whether the file contains the names of the variables.
skip
integer; the number of lines skiped before data is read.
sep
character; the field separator string.
dec
character; used in the file for decimal points.
na
character; string interpreted as NA values.
quote
character; the set of quoting characters.
comment
character; comment character.
encoding
character; encoding that was assumed for input strings, see Encoding.
str.as.fact
logical; if TRUE, character variables are converted to factors.

Details

This GUI is a wrapper for the read.table function. Data connections are defined as the path to the file to be opened, a complete URL (e.g. http://, ftp:// or file://), or windows clipboard. Files are limited to text format (e.g., ‘.tsv’ ‘.csv’, or ‘.txt’); however, they can be compressed by gzip, bzip2, or xz with additional extension ‘.gz’, ‘.bz2’, or ‘.xz’, respectively.

Conversion specification formats are the character representation of object types used to: identify column classes prior to reading in data, and format values for printing. Conversion specifications are based on C-style string formatting commands for numeric, integer, and character object classes, see sprintf; for example, a format string of "%.5f" applied to the mathematical constant pi results in "3.14159". Calendar date and time objects of class POSIXct are defined by the ISO C99 / POSIX standard, see strftime; for example, "02/26/2010 02:05:39 PM" is represented using "%d/%m/%Y %I:%M:%S %p".

Comments located above data records and header lines are preserved; all other comments are ignored. Requires the specification of a comment character.

Performance issues associated with reading in large files can be alleviated by specifying formats in a header line, and giving the maximum number of rows to read in.

See Also

read.table