MinMax - Output minimum or maximum input value

Library

Math Operations

Description

The MinMax block outputs either the minimum or the maximum element or elements of the inputs. You can choose the function to apply by selecting one of the choices from the Function parameter list.

If the block has one input port, the input must be a scalar or a vector. The block outputs a scalar equal to the minimum or maximum element of the input vector.

If the block has multiple input ports, all nonscalar inputs must have the same dimensions. The block expands any scalar inputs to have the same dimensions as the nonscalar inputs. The block outputs a signal having the same dimensions as the input. Each output element equals the minimum or maximum of the corresponding input elements.

The MinMax block ignores any input value that is NaN, except when every input value is NaN. When all input values are NaN, the output is NaN, either as a scalar or the value of each output vector element.

Data Type Support

The MinMax block accepts and outputs real signals of the following data types:

Floating point
Built-in integer
Fixed point

For more information, see Data Types Supported by Simulink in the Simulink documentation.

Parameters and Dialog Box

The Main pane of the MinMax block dialog box appears as follows:

Function: Specify whether to apply the function min or max to the input.
Number of input ports: Specify the number of inputs to the block.
Enable zero-crossing detection: Select to enable zero-crossing detection. For more information, see Zero-Crossing Detection.
Sample time (-1 for inherited): Specify the time interval between samples. To inherit the sample time, set this parameter to -1. See How to Specify the Sample Time in the online documentation for more information.

The Signal Attributes pane of the MinMax block dialog box appears as follows:

Require all inputs to have the same data type

Select this check box to require that all inputs have the same data type.

Output minimum

Specify the minimum value that the block should output. The default value is [] (unspecified). Simulink software uses this value to perform:

Simulation range checking (see Signal Ranges)
Automatic scaling of fixed-point data types

Output maximum

Specify the maximum value that the block should output. The default value is[] (unspecified). Simulink software uses this value to perform:

Simulation range checking (see Signal Ranges)
Automatic scaling of fixed-point data types

Output data type

Specify the output data type. You can set it to:

A rule that inherits a data type, for example, Inherit: Inherit via back propagation
The name of a built-in data type, for example, single
The name of a data type object, for example, a Simulink.NumericType object
An expression that evaluates to a data type, for example, fixdt(1,16,0)

Click the Show data type assistant button to display the Data Type Assistant, which helps you set the Output data type parameter.

See Specifying Block Output Data Types for more information.

Lock output data type setting against changes by the fixed-point tools

Select to lock the output data type setting of this block against changes by the Fixed-Point Tool and the Fixed-Point Advisor. For more information, see Fixed-Point Tool and Fixed-Point Advisor in the Simulink Fixed Point documentation.

Integer rounding mode

Specify the rounding mode for fixed-point operations. For more information, see Rounding in the Simulink Fixed Point User's Guide.

Saturate on integer overflow

Action	Reasons for Taking This Action	What Happens for Overflows	Example
Select this check box.	Your model has possible overflow and you want explicit saturation protection in the generated code.	Overflows saturate to either the minimum or maximum value that the data type can represent.	An overflow associated with a signed 8-bit integer can saturate to -128 or 127.
Do not select this check box.	You want to optimize efficiency of your generated code. You want to avoid overspecifying how a block handles out-of-range signals. For more information, see Checking for Signal Range Errors.	Overflows wrap to the appropriate value that is representable by the data type.	The number 130 does not fit in a signed 8-bit integer and wraps to -126.

Action

Reasons for Taking This Action

What Happens for Overflows

Example

Select this check box.

Your model has possible overflow and you want explicit saturation protection in the generated code.

Overflows saturate to either the minimum or maximum value that the data type can represent.

An overflow associated with a signed 8-bit integer can saturate to -128 or 127.

Do not select this check box.

You want to optimize efficiency of your generated code.

You want to avoid overspecifying how a block handles out-of-range signals. For more information, see Checking for Signal Range Errors.

Overflows wrap to the appropriate value that is representable by the data type.

The number 130 does not fit in a signed 8-bit integer and wraps to -126.

When you select this check box, saturation applies to every internal operation on the block, not just the output or result. In general, the code generation process can detect when overflow is not possible. In this case, the code generator does not produce saturation code.

Examples

The sldemo_fuelsys model shows how to use the MinMax block.

In the Engine Gas Dynamics/Throttle & Manifold/Throttle subsystem, the MinMax block uses the min operator:

In the Engine Gas Dynamics/Mixing & Combustion subsystem, the MinMax block uses the max operator:

For more information, see the model description.

Characteristics

Direct Feedthrough	Yes
Sample Time	Specified in the Sample time parameter
Scalar Expansion	Yes, of the inputs
Dimensionalized	Yes
Multidimensionalized	Yes
Zero-Crossing Detection	Yes, if enabled

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