Data types

When entering properties for the model objects, there are a number of different data types that are used in the Train Noise Expert user interface.

Library item choice

Here the library item assigned to this model object can be chosen. New library items can be created and renamed from the library list. When selecting a library item, all the values in the property table will be updated accordingly.


A selection can be made from a list of items. Sometimes this will influence whether other properties are visible.


For numbers, Train Noise Expert will automatically convert the input into the correct format and precision. Scientific notation is used for some values, where 3.23e6 is equivalent to 3.23 x 106 (i.e. 3230000). Note that the standard convention in Train Noise Expert for decimals is a point ( . ) rather than a comma ( , ). Invalid values are not allowed.


Text is input in either single line entries or multiline text boxes. For many properties, special characters are not allowed, so it is usually recommended to only use alphanumeric text.

File location

File locations can be entered directly into these fields, or alternatively it is possible to use the folder button to browse to the appropriate file.
File location paths can be absolute (e.g. C:\Users\userID\folder\, but care should be taken if the project is to be used on another computer, as this file path might no longer be valid.
Alternatively, the path to the project folder can be represented by ‘<<‘. A file stored in the project folder could therefore be referenced by ‘<<\’. Similarly, the default application folder (which contains some example input files) is represented by ‘>>’. If the file specified in this field does not exist, then the field will be shown with a   red border . This file path must be corrected before running any calculations, or else it is likely that errors will occur. The input data associated with the given file may be viewed by clicking on the plot button to the right of the folder button. This will launch a small window with tabs to view a simple plot of the data, a table of the data, and the raw data file content. In the case of roughness or track decay rate data, the TSI values are also shown as a dashed grey line.