Special Characters Window

The Special Characters window of the allows you to define characters or strings that the data loader interprets in pre-defined ways, often as a missing value or a value below detection limit. This is useful when, for example, you use a large negative number (such as -99999) or the '-' character to define missing numeric values, or use a string (such as bdl or <0.0001) to define a sample's value as below detection limit.

Without entries in Special Characters window the data loading may generate errors (reading non-numeric values as numeric data) or may include wrong samples (for example, -99999). In some cases you can subsequently filter these values out, but it is recommended to include entries in this library to catch such occurrences.

See how to Substitute Values Using the Special Characters Window.