Create Fixed-Point Objects in MATLAB

fi and numerictype for fixed-point data creation

You can create fixed-point data using the Fixed-Point Designer™ fi object. Within the fi constructor, you can specify numerictype and fimath properties. Each fi object has an associated numerictype object. The numerictype object stores information about the fi object including word length, fraction length, and signedness. The numerictype object is equivalent to the fixdt object in Simulink^®.

Functions

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Construct Fixed-Point Numeric Objects

`fi`	Construct fixed-point numeric object
`sfi`	Construct signed fixed-point numeric object
`ufi`	Construct unsigned fixed-point numeric object

Fixed-Point Math Settings

`fimath`	Set fixed-point math settings
`globalfimath`	Configure global fimath and return handle object
`removefimath`	Remove fimath object from `fi` object
`removeglobalfimathpref`	Remove global fimath preference
`resetglobalfimath`	Set global fimath to MATLAB factory default
`setfimath`	Attach fimath object to `fi` object

Fixed-Point Preferences

`fipref`	Set fixed-point preferences
`savefipref`	Save `fi` preferences for next MATLAB session
`isfipref`	Determine whether input is `fipref` object

Properties of `fi` Objects

`lowerbound`	Lower bound of range of `fi` object
`lsb`	Scaling of least significant bit of `fi` object, or value of least significant bit of `quantizer` object
`range`	Numerical range of `fi` or `quantizer` object
`upperbound`	Upper bound of range of `fi` object
`sort`	Sort elements of real-valued `fi` object in ascending or descending order

Objects and Properties

`fixed.aggregateType`	Compute aggregate numerictype
`get`	Property values of object
`isequal`	Determine whether real-world values of two `fi` objects are equal, or determine whether properties of two `fimath`, `numerictype`, or `quantizer` objects are equal
`reset`	Reset objects to initial conditions
`set`	Set or display property values for `quantizer` objects
`mat2str`	Convert matrix to string
`tostring`	Convert `fi`, `fimath`, `numerictype`, or `quantizer` object to string

Classes

numerictype Construct an embedded.numerictype object describing fixed-point or floating-point data type

Topics

Construct Fixed-Point Numeric Objects

Create Fixed-Point Data in MATLAB

Fixed point basics.

Performing Fixed-Point Arithmetic

Performing fixed-point arithmetic.

View Fixed-Point Data

fi object display settings used in code examples.

Ways to Construct fi Objects

Creation of fi objects.

Fixed-Point Versus Built-in Integer Types

Differences between fixed-point data types and built-in integer data types in MATLAB^®.

fi Object Functions

Functions that operate directly on fi objects.

fi Object Properties

Defines the fi object properties.

Fixed-Point Math Settings

fimath Object Construction

Creation of fimath objects.

fimath Object Properties

Properties and property settings associated with fimath objects.

fimath Properties Usage for Fixed-Point Arithmetic

Fixed-point arithmetic using fimath objects to control the results.

fimath for Sharing Arithmetic Rules

Using a fimath object to share modular arithmetic information among multiple fi objects.

fimath for Rounding and Overflow Modes

Order setting for overflow action and rounding method.

fimath ProductMode and SumMode

Differences among the different settings of the ProductMode and SumMode properties.

How Functions Use fimath

Functions that ignore or discard fimath.

Fixed-Point Preferences

Set fi Object Display Preferences Using fipref

Examples of using fipref objects to set display preferences for fi objects.

Data Type Override Preferences Using fipref

Data type override using the fipref object.

Underflow and Overflow Logging Using fipref

Examples of using fipref objects to set logging preferences for fi objects.

Numeric Type Information

numerictype Object Construction

Construction of numerictype objects.

numerictype Object Properties

Properties and property settings associated with numerictype objects.

numerictype of Fixed-Point Objects

Fields and settings for the numerictype object.

numerictype Objects Usage to Share Data Type and Scaling Settings of fi objects

Example of using a numerictype object to share modular data type and scaling information among multiple fi objects.

Applications

Fixed-Point Design Exploration in Parallel

This example shows how to explore and test fixed-point designs by distributing tests across many computers in parallel.

Real-Time Image Acquisition, Image Processing, and Fixed-Point Blob Analysis for Target Practice Analysis

Acquire real-time images from a webcam, process the images using fixed-point blob analysis, and determine world coordinates to score target practice using a laser pistol.

Fixed-Point Filter Design in MATLAB (DSP System Toolbox)

This example shows how to design filters for use with fixed-point input.