You can customize most Simulink® blocks by specifying values for block attributes. Some attributes such as block name and block foreground color are common to Simulink blocks. Other attributes are block-specific, such as the gain value of a Gain block.
Simulink represents block attributes as three types of parameters:
Block properties: Specify attributes such as block description, block execution order, block annotations, and block callback functions. You specify a block property by setting its associated block parameter. For example, to set the foreground color of a block to red, you set the value of its foreground color parameter to the string 'red'.
Mathematical parameters: Determine how a block behaves during simulation. Set values for these parameters to control block output. Examples of these parameters include the gain value of the Gain block, dimensions of a lookup table, and the initial condition of a Unit Delay block.
You can specify the following types of values for mathematical parameters.
Expressions with variables
When Simulink compiles a model, it sets the compiled values of the parameters to the result of evaluating the expressions.
Configuration parameters: Determine how a block is configured during an update diagram. Setting these parameters controls attributes such as sample time, dimensionality, and start time.