EditFunction: GUI: Function Editor

In USGS-R/RSurvey: Geographic Information System Application

Description

A graphical user interface (GUI) for defining functions in the R language.

Usage

EditFunction(cols, index = NULL, fun = NULL, value.length = NULL,
  value.class = NULL, win.title = "Edit Function", parent = NULL)

Arguments

cols	list. y
index	integer. An element index number in cols.
fun	character. Existing function, only used if index = NULL
value.length	integer. Required length for the evaluated function.
value.class	character. Required class for the evaluated function.
win.title	character. String to display as the title of the dialog box.
parent	tkwin. GUI parent window

Details

This GUI is appropriate for deriving new variables in a pre-existing data frame or query building.

Value

Returns an object of class list with the following components:

fun	user defined function (when evaluated, this string must be parseable).
class	object class for the evaluated function.
summary	default summary for the evaluated function.
sample	first non-missing value for the evaluated function.

Author(s)

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

See Also

EvalFunction

Examples

## Not run: 
  d <- list(x = 1:10, y = 10:1)
  Data("data.raw", d)
  cols <- list()
  cols[[1]] <- list(id = "X", index = 1, fun = "\"X\"")
  cols[[2]] <- list(id = "Y", index = 2, fun = "\"Y\"")
  cols[[3]] <- list(id = "New Variable", fun = "\"X\" + \"Y\"")
  EditFunction(cols, index = 3)

## End(Not run)

USGS-R/RSurvey documentation built on May 9, 2019, 6:10 p.m.