fxptdlg

Propose fraction lengths

Use range information and propose fraction lengths for model objects.

Action

Use this button to perform the first phase of the automatic data typing procedure, in which the Fixed-Point Tool uses range information for model objects—from design minimum and maximum values the objects specify explicitly, or from logged minimum and maximum values that occur during simulation, or from derived minimum and maximum values. Based on these values, the tool proposes fraction lengths for blocks whose:

•Lock output data type setting against changes by the fixed-point tools or Lock data type settings against changes by the fixed-point tools check box is cleared.

•Data type specifies a generalized fixed-point number.

The Fixed-Point Tool lists its scaling proposals in the Contents pane. The tool alerts you to potential scaling issues for each object in the list by displaying a green, yellow, or red icon, as shown here:

The proposed scaling poses no issues for this object.

The proposed scaling poses potential issues for this object. Open the Autoscale Information dialog box to review these issues.

The proposed scaling will introduce data type errors if applied to this object. Open the Autoscale Information dialog box for details about how to resolve these issues.

Command-Line Alternative

No command line alternative available.

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fxptdlg

Propose word lengths

Use range information and propose word lengths for model objects.

Action

Use this button to perform the first phase of the automatic data typing procedure, in which the Fixed-Point Tool uses range information for model objects—from design minimum and maximum values the objects specify explicitly, or from logged minimum and maximum values that occur during simulation, or from derived minimum and maximum values. Based on these values, the tool proposes word lengths for blocks whose:

•Lock output data type setting against changes by the fixed-point tools or Lock data type settings against changes by the fixed-point tools check box is cleared.

•Data type specifies a generalized fixed-point number.

The Fixed-Point Tool lists its data type proposals in the Contents pane. The tool alerts you to potential issues for each object in the list by displaying a green, yellow, or red icon, as shown here:

The proposed data type poses no issues for this object.

The proposed data type poses potential issues for this object. Open the Result Details dialog box to review these issues.

The proposed data type will introduce errors if applied to this object. Open the Result Details dialog box for details about how to resolve these issues.

Command-Line Alternative

No command line alternative available.

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fxptdlg

Propose data types

Propose fraction lengths for specified word lengths

Select to propose fraction lengths for the word lengths specified in the model.

Note This parameter appears only if the Automatic data typing for selected system Settings pane is displayed.

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fxptdlg

Propose word lengths for specified fraction lengths

Select to propose word lengths for the fraction lengths specified in the model.

Note This parameter appears only if the Automatic data typing for selected system Settings pane is displayed.

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fxptdlg

Default data type for all floating-point signals

Specifies the default data type to use for all floating-point signals

Use to change the floating-point data types in the model to fixed point.

Settings

Default:

Remain floating-point

Does not change the data type of floating-point signals.

Select this option if you are using the Fixed-Point Tool to derive minimum and maximum values for the model. To propose data types for the model, you must set the default data type to be a built-in integer or fixed-point data type.

Same as embedded hardware integer

Sets the default data type for all floating-point signals to the integer type specified for the target hardware.

Select this option if your target hardware is a microprocessor.

int8

Sets the default data type for all floating-point signals to int8.

int16

Sets the default data type for all floating-point signals to int16.

int32

Sets the default data type for all floating-point signals to int32.

fixdt(1,16,4)

Sets the default data type for all floating-point signals to the fixed-point data type specified by fixdt. You can modify the parameters provided to fixdt to specify signedness, word length and fraction length.

Dependency

This parameter appears only if you click the Configure link on the

Automatic data typing for selected system Settings pane.

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fxptdlg

Derived min/max

Propose fraction or word lengths based on design and derived minimum and maximum information.

Settings

Default: On

On

Propose fraction or word lengths based on derived minimum and maximum values, but only for blocks that do not specify design minimum or maximum values using, for example, Output minimum and Output maximum parameters.

If Simulation min/max is also selected, the Fixed-Point Tool bases its proposal on both the derived and simulation min/max values and the proposed data types cover the union of the derived range and the simulation range.

Off

Ignore derived minimum and maximum values when proposing fraction lengths.

Command-Line Alternative

No command line alternative available.

Dependency

This parameter appears only if you click the Configure link on the

Automatic data typing for selected system Settings pane.

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