Chapter 11. Options, arguments and path-searching

Table of Contents
gretl
gretlcli
Path searching

gretl

gretl (under MS Windows, gretlw32.exe)[1]

— Opens the program and waits for user input.

gretl datafile

— Starts the program with the specified datafile in its workspace. The data file may be in native gretl format, CSV format, or BOX1 format (see Chapter 4 above). The program will try to detect the format of the file and treat it appropriately. See also the Section called Path searching below for path-searching behavior.

gretl --help (or gretl -h)

— Print a brief summary of usage and exit.

gretl --version (or gretl -v)

— Print version identification for the program and exit.

gretl --english (or gretl -e)

— Force use of English instead of translation.

gretl --run scriptfile (or gretl -r scriptfile)

— Start the program and open a window displaying the specified script file, ready to run. See the Section called Path searching below for path-searching behavior.

gretl --db database (or gretl -d database)

— Start the program and open a window displaying the specified database. If the database files (the .bin file and its accompanying .idx file — see the Section called Binary databases in Chapter 4) are not in the default system database directory, you must specify the full path.

gretl --dump (or gretl -c)

— Dump the program's configuration information to a plain text file (the name of the file is printed on standard output). May be useful for trouble-shooting.

Various things in gretl are configurable under the "File, Preferences" menu.

There are also some check boxes. Checking the "expert" box quells some warnings that are otherwise issued. Checking "Tell me about gretl updates" makes gretl attempt to query the update server at start-up. Unchecking "Show gretl toolbar" turns the icon toolbar off. If your native language setting is not English and the local decimal point character is not the period ("."), unchecking "Use locale setting for decimal point" will make gretl use the period regardless.

Finally, there are some binary choices: Under the "Open/Save path" tab you can set where gretl looks by default when you go to open or save a file — either the gretl user directory or the current working directory. Under the "Data files" tab you can set the default filename suffix for data files. The standard suffix is .gdt but if you wish you can set this to .dat, which was standard in earlier versions of the program. If you set the default to .dat then data files will be saved in the "traditional" format (see Chapter 4). Also under the "Data files" tab you can select the action for the little folder icon on the toolbar: whether it should open a listing of the data files associated with Ramanathan's textbook, or those associated with Wooldridge's text.

Under the "General" tab you may select the algorithm used by gretl for calculating least squares estimates. The default is Cholesky decomposition, which is fast, relatively economical in terms of memory requirements, and accurate enough for most purposes. The alternative is QR decomposition, which is computationally more expensive and requires more temporary storage, but which is more accurate. You are unlikely to need the extra accuracy of QR decomposition unless you are dealing with very ill-conditioned data and are concerned with coefficient or standard error values to more than 7 digits of precision.[2]

Settings chosen in this way are handled differently depending on the context. Under MS Windows they are stored in the Windows registry. Under the gnome desktop they are stored in .gnome/gretl in the user's home directory. Otherwise they are stored in a file named .gretlrc in the user's home directory.

Notes

[1]

On Linux, a "wrapper" script named gretl is installed. This script checks whether the DISPLAY environment variable is set; if so, it launches the GUI program, gretl_x11, and if not it launches the command-line program, gretlcli.

[2]

The option of using QR decomposition can also be activated by setting the environment variable GRETL_USE_QR to any non-NULL value.