importTxt: Import grid data from a text file.

Description

You can define a grid using a standard text editor and saving it as a .txt file. The Details section describes the required format of the .txt file. However, you may also consider using the Excel format instead, as it has a more intuitive format (see importExcel()).

Usage

importTxt(file, dir = NULL, min = NULL, max = NULL)

Value

A single repgrid object in case one file and a list of repgrid objects in case multiple files are imported.

Arguments

file: A vector of filenames including the full path if file is not in current working directory. File can also be a complete URL. The file suffix has to be .txt.
dir: Alternative way to supply the directory where the file is located (default NULL).
min: Optional argument (numeric, default NULL) for minimum rating value in grid.
max: Optional argument (numeric, default NULL) for maximum rating value in grid.

Details

The .txt file has to be in a fixed format. There are three mandatory blocks each starting and ending with a predefined tag in uppercase letters. The first block starts with ELEMENTS and ends with END ELEMENTS and contains one element in each line. The other mandatory blocks contain the constructs and ratings (see below). In the block containing the constructs the left and right pole are separated by a colon (:). To define missing values use NA like in the example below. One optional block contains the range of the rating scale used defined by two numbers. The order of the blocks is arbitrary. All text not contained within the blocks is discarded and can thus be used for comments.

The content of a sample .txt file is shown below. The package also contains a sample file (see Examples).

---------------- sample .txt file -------------------
    Note: anything outside the tag pairs is discarded
ELEMENTS
element 1
element 2
element 3
END ELEMENTS
CONSTRUCTS
left pole 1 : right pole 1
left pole 2 : right pole 2
left pole 3 : right pole 3
left pole 4 : right pole 4
END CONSTRUCTS
RATINGS
1 3 2
4 1 1
1 4 4
3 1 1
END RATINGS
RANGE
1 4
END RANGE
------------------ end of file ------------------

Note that the maximum and minimum value has to be defined using the min and max arguments if no RANGE block is contained in the data file. Otherwise the scaling range is inferred from the available data and a warning is issued as the range may be erroneous. This may effect other functions that depend on knowing the correct range and it is thus strongly recommended to set the scale range correctly.

Examples

Run this code

# Import a .txt file delivered along with the package
file <- system.file("extdata", "grid_01.txt", package = "OpenRepGrid")
rg <- importTxt(file)

if (FALSE) {
# To see the structure of the Excel file try to open it as follows.
# May not work on all systems.
file.show(file)
}

# Import more than one .txt file
files <- system.file("extdata", c("grid_01.txt", "grid_02.txt"), package = "OpenRepGrid")
rgs <- importTxt(files)