Expression

The expression block can be used to specify an arbitrary function of the model parameters and /or the quantity in other blocks (such as compartments and lookup tables. The value of this block is available for use during the simulations.

Creating an expression

From the Projects window

Expand the Project to which you wish to add the expression by clicking the + symbol next to it. Right-click on ‘Blocks’, or a sub-system in ‘Blocks’, and select Expression from the pop-up menu.

From the Model window

Right click an empty diagonal cell of the matrix and select Expression from the the pop-up menu.

From the Blocks window

Place the mouse cursor over the table and right-click on it. Select Create | Expression from the pop-up menu, or
In the title bar, select Expression from the Type drop-down list and click on the button.

Editing an expression

Note	Most block properties can be edited directly in the blocks window.

The block editor is shown by right-clicking the block in a window and selecting Edit. In the Blocks window, you can also show the block editor by selecting the block and clicking the button, or by double-clicking the right-most “validation” column of the block.

The block editor has three tabs:

Properties

This page lets you edit basic properties such as name, sub-system and base unit. See editing properties for more information.

Matrix

This page lets you edit the visual properties of the block in the Model window. See Editing matrix properties for more information.

Values

Note	When entering an expression, you can also enter names of objects that are not yet created and let Ecolego use automatic object creation to define them.

This page lets you specify the algebraich expression and other index specific properties.

Dimension - You can specify the dimension of the block by using the Type drop down list. Depending on the dimension the index drop down lists are activated.

Data