fimath - Construct fimath object

Syntax

F = fimath
F = fimath(...'PropertyName',PropertyValue...)

Description

You can use the fimath constructor function in the following ways:

• F = fimath creates a fimath object with the same properties as the current global fimath. The factory default configuration of the global fimath has the following properties:

               RoundMode: nearest
            OverflowMode: saturate
             ProductMode: FullPrecision
    MaxProductWordLength: 128
                 SumMode: FullPrecision
        MaxSumWordLength: 128
  

  You can request a handle object to the global fimath and change any of its property values using globalfimath. For more information about configuring the global fimath, see Working with the Global fimath in the Fixed-Point Toolbox User's Guide.

• F = fimath(...'PropertyName',PropertyValue...) allows you to set the attributes of a fimath object using property name/property value pairs. All property names that you do not specify in the constructor get their values from the current global fimath.

The properties of the fimath object are listed below. These properties are described in detail in fimath Object Properties in the Properties Reference.

• CastBeforeSum — Whether both operands are cast to the sum data type before addition

  Note   This property is hidden when the SumMode is set to FullPrecision.

• MaxProductWordLength — Maximum allowable word length for the product data type

• MaxSumWordLength — Maximum allowable word length for the sum data type

• OverflowMode — Overflow-handling mode

• ProductBias — Bias of the product data type

• ProductFixedExponent — Fixed exponent of the product data type

• ProductFractionLength — Fraction length, in bits, of the product data type

• ProductMode — Defines how the product data type is determined

• ProductSlope — Slope of the product data type

• ProductSlopeAdjustmentFactor — Slope adjustment factor of the product data type

• ProductWordLength — Word length, in bits, of the product data type

• RoundMode — Rounding mode

• SumBias — Bias of the sum data type

• SumFixedExponent — Fixed exponent of the sum data type

• SumFractionLength — Fraction length, in bits, of the sum data type

• SumMode — Defines how the sum data type is determined

• SumSlope — Slope of the sum data type

• SumSlopeAdjustmentFactor — Slope adjustment factor of the sum data type

• SumWordLength — Word length, in bits, of the sum data type

Examples

Example 1

Type

F = fimath

to create a default fimath object. If you are using the factory default setting of the global fimath, you get the following output:

F =
 
             RoundMode: nearest
          OverflowMode: saturate
           ProductMode: FullPrecision
  MaxProductWordLength: 128
               SumMode: FullPrecision
      MaxSumWordLength: 128

Example 2

You can set properties of fimath objects at the time of object creation by including properties after the arguments of the fimath constructor function. For example, to set the overflow mode to saturate and the rounding mode to convergent,

F = fimath('OverflowMode','saturate',...
           'RoundMode','convergent')
 
F =
 
             RoundMode: convergent
          OverflowMode: saturate
           ProductMode: FullPrecision
  MaxProductWordLength: 128
               SumMode: FullPrecision
      MaxSumWordLength: 128

See Also

fi | fipref | globalfimath | numerictype | quantizer | removeglobalfimathpref | resetglobalfimath | saveglobalfimathpref

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