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Simulink 中的迭代定点转换


定点工具是一个用户界面,它自动执行在 Simulink® 模型中指定定点数据类型的任务。该工具根据仿真、派生或设计范围收集模型对象的范围数据。在 Iterative Fixed-Point Conversion 工作流中,该工具会基于这些范围数据建议能够最大化精度和覆盖范围的定点数据类型。然后,您可以检查数据类型建议,并有选择地将它们应用于模型中的对象。如果不满足设计要求,您可以调整数据类型建议设置,可视化其效果,并进行迭代,直到系统满足您的要求。

要将模型转换为定点,请按照Iterative Fixed-Point Conversion Using the Fixed-Point Tool中的步骤操作。有关完整转换过程的示例,请参阅Convert Floating-Point Model to Fixed Point

DataTypeWorkflow.Converter 对象及其关联的对象函数是定点工具中 Iterative Fixed-Point Conversion 的命令行替代项。


定点工具Convert a floating-point model to a fixed-point model


fxptdlgOpen the Fixed-Point Tool

DataTypeWorkflow.ConverterCreate fixed-point converter object
DataTypeWorkflow.findDecoupledSubsystemsGet a list of subsystems to replace with an approximation
DataTypeWorkflow.ProposalSettingsProposal settings object for data type proposals
DataTypeWorkflow.ResultObject containing run result information
DataTypeWorkflow.VerificationResultVerification results after converting a system to fixed point



Best Practices for Fixed-Point Conversion Workflow

Use best practices when converting a model to fixed point.

Iterative Fixed-Point Conversion Using the Fixed-Point Tool

Use the Fixed-Pint Tool to convert a system from floating point to fixed point.

Convert Floating-Point Model to Fixed Point

Use the Fixed-Point Tool to convert a floating-point model to fixed point.

Rescale a Fixed-Point Model

Use the Fixed-Point Tool to autoscale fixed-point data types in a feedback model.

The Command-Line Interface for the Fixed-Point Tool

Learn the differences between the command-line interface workflow and the Fixed-Point Tool workflow.


Use the Fixed-Point Tool to Prepare a System for Conversion

Use the Fixed-Point Tool to check the system under design for compatibility with the conversion process.

Specify Behavioral Constraints

Use signal tolerances and model verification blocks to verify behavior of fixed-point implementation.


Fixed-Point Instrumentation and Data Type Override

Fixed-point instrumentation and data type override settings for gathering range information on your model.

Choosing a Range Collection Method

Choose from three methods for collecting ranges on which to base data type proposals.

How Range Analysis Works

Learn how the static analysis derives range information.

Prevent the Fixed-Point Tool from Overriding Integer Data Types

Maintain integer data types in your model when using data type override.


How the Fixed-Point Tool Proposes Data Types

Learn how the Fixed-Point Tool proposes data types based on collected ranges and proposal settings.

Propose Data Types For Merged Simulation Ranges

Use the Fixed-Point Tool to merge results from multiple simulations, and propose data types based on the merged results.

How Hardware Implementation Settings Affect Data Type Proposals

Use the Fixed-Point Tool to propose word lengths for a model that implements a simple moving average algorithm.


Convert a Referenced Model to Fixed Point

Use the Fixed-Point Tool to log simulation minimum and maximum values for referenced models and proposes data types based on a union of the collected ranges.

Bus Objects in the Fixed-Point Workflow

Learn how data type override behaves with bus objects, and how data types are determined for bus objects.

Autoscaling Data Objects Using the Fixed-Point Tool

Use the Fixed-Point Tool to convert a model that uses data objects for data type specification to fixed point.

Convert MATLAB Function Block to Fixed Point

Use the Fixed-Point Tool to convert a MATLAB® Function block to fixed-point.


Control Views in the Fixed-Point Tool

Information filtering, sorting, and analysis in the Fixed-Point Tool.

View Simulation Results

Use the Simulation Data Inspector to view simulation results and compare runs to verify your fixed-point design.

Explore Multiple Floating-Point to Fixed-Point Conversions

Iteratively explore different proposal settings to find the best floating point to fixed-point conversion.

Model Multiple Data Type Behaviors Using a Data Dictionary

Example showing how to use referenced data dictionaries to store multiple sets of data types for a model.


Blocks That Do Not Support Fixed-Point Data Types

Troubleshoot blocks that are not supported for fixed-point conversion.

Models That Might Cause Data Type Propagation Errors

Know which modeling practices could cause data type propagation errors after autoscaling.

Resolve Range Analysis Issues

Troubleshoot range analysis issues.

Fixing Design Range Conflicts

Avoid specifying conflicting design minimum and maximum values in your model.

Insufficient Design Range Information

Troubleshoot errors caused by insufficient design range information by providing additional input design minimum and maximum values.

Providing More Design Range Information

Troubleshoot insufficient design range information that prevents successful derived range analysis.

Troubleshoot Range Analysis of System Objects

Reconfigure a System Object, if necessary, so that ranges can be derived for the model.

The Fixed-Point Tool did not Propose Data Types

Troubleshoot when the Fixed-Point Tool does not propose data types.

Data Type Mismatch and Structure Initial Conditions

Example showing how to replace a structure initial condition with a Simulink.Parameter object.

Data Type Propagation Errors After Applying Proposed Data Types

Troubleshoot when the Fixed-Point Tool proposes data types that are not compatible with the model.