ImportText: GUI: Import Data from Text File

In RSurvey: Geographic Information System Application

Description

A graphical user interface (GUI) for reading table formatted data from a text file.

Usage

ImportText(parent = NULL)

Arguments

parent

tkwin. GUI parent window

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://, https://, 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 " 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 "

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.

Value

Sets the following components in Data:

data.raw	imported data table.
cols	a list with length equal to the current number of data variables. Each component in cols is linked to a specific variable, see ManageVariables.
comment	vector of comment strings
import	a list of saved GUI options

Components of the import list include:

source	a vector of length 2 that includes the pathname of the text file and access date.
fmts	indicates whether the file contains the conversion specification format strings of the variables.
cols	indicates whether the file contains the names of the variables.
skip	Number of lines skipped before data is read.
sep	Field separator string
dec	Used in the file for decimal points.
na	String interpreted as NA values.
quote	Set of quoting characters
comment	Comment character
encoding	Encoding that was assumed for input strings, see Encoding.
str.as.fact	If true, character variables are converted to factors.

Note

Requires the Tcl package Tktable.

Author(s)

J.C. Fisher, U.S. Geological Survey, Idaho Water Science Center

See Also

read.table

Examples

## Not run: 
  ImportText()

## End(Not run)

RSurvey documentation built on May 2, 2019, 3:28 p.m.