# Using the DataNavigator

LEONARDO includes a special interface to ENVI-met data files which allows a simple navigation through the data. This interface is called DataNavigator.
Start the DataNavigator by selecting menu entry “Tools | DataNavigator”.

Your screen should contain the following:

### Select ENVI-met File

Click on the folder symbol and select an ENVI-met data file.
LEONARDO will read the information file (.EDI) and creates a list of all variables stored in the file. Also the title and the dimension of the simulation data are displayed at the bottom of the list.
Up to this point, no data have been read into the map.

### Select Variables to Display

LEONARDO uses 5 internal layers for displaying data and each ENVI-met file contains a collection of several data. In order to bring those two ends together, you must assign the variables in the list to the corresponding map layer.
To assign a variable to a map layer, select first the variable in the list

and then click on the assign button of the layer.

This will tell LEONARDO to extract the selected variable out of the data file and put it on the selected layer (Pot. Temperature on Data Layer in this case)

### Select Type of Section

To create a two-dimensional map out of a three-dimensional data set you must specify the type and the position of a cross section.
If your selected data is only two-dimensional, no cross sections can be selected.

Select the type of section you need:

„**X-Y**" for a horizontal view,
„**X-Z**" for a vertical view from the front and
„**Y-Z**" for a vertical view from the left side.

Depending on the type of section, one coordinate remains constant, for example the height z in an horizontal X-Y cut.
Define the cut position by setting the “Cut at…” edit field. The actual cut position is given in grids and in absolute meter.

### Extracting Data and Build Map

After you have selected all variables to be imported into the map, you can extract the data from the ENVI-met file.
To extract a 2D cut, press the “Extract 2D cut”-Button

Next step: Fine-Tuning the Map