# Logger items

Always triple-check whether OpenSesame has logged all relevant variables!

The logger item is the primary way to log your data to file.

## Selecting variables

In the logger item you can indicate which variables you wish to log. By default the logger tries to auto-detect and log all variables. This is a safe bet, but results in large datafiles, with lots of unnecessary information. If you deselect the auto-detect option, you can select variables from the list, which contains all (global) variables that OpenSesame is aware of. If, for some reason, the variable that you want to log does not appear in the list, you can add it using the 'Add custom variable' button. If you are unsure which variables you want to log, you can click on the Smart select button, which will select all variables that are likely to be of interest.

## Options

- Use 'NA' for variables that have not been set indicates that the logger should not throw an exception when a variable has not been set. This can be useful when you want to log a variable that has not been set the first time that the logger item is called.
- Automatically detect and log all variables indicates that the logger should auto-detect and log all variables.
- Allow secial characters in log file indicates that the logger should not convert special characters to U+XXXX notation. This makes the logfile easier to read if you use many special characters or a non-western font.
- Put quotes around values indicates that fields in the logfile should be put in quotes.

## Format of the logfile

The logfile is in plain-text, comma-separated format. This format can be viewed in most text-editors (although Windows Notepad may not handle the line-endings properly) and spreadsheets.

## Merging data files

If you prefer to have all participant data in a single spreadsheet, you can merge the OpenSesame logfiles using the online spreadsheet merger.