quantize

Quantize fi values using fixed.Quantizer object

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quantize and fixed.Quantizer are not recommended. Use cast, zeros, ones, eye, or subsasgn instead. For more information, see Compatibility Considerations.

Syntax

y = quantize(q,x)

Description

y = quantize(q,x) uses the fixed.Quantizer object q to quantize x. x can be any fixed-point fi number except a Boolean value.

  • If x is a scaled double, the data of the output y will be the same as the data of the input x. Only the fixed-point settings of y will change.

  • When x is a double or single, then y = x. This functionality allows you to share the same code for both floating-point data types and fixed-point fi data types when quantizers are present.

example

Examples

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Use fixed.Quantizer to reduce the word length that results from adding two fixed-point numbers.

q = fixed.Quantizer
x1 = fi(0.1,1,16,15);
x2 = fi(0.8,1,16,15);
y  = quantize(q,x1+x2)
q = 

  fixed.Quantizer with properties:

                   Signed: 1
               WordLength: 16
    SlopeAdjustmentFactor: 1
            FixedExponent: -15
                     Bias: 0
               Signedness: 'Signed'
                    Slope: 3.0518e-05
           FractionLength: 15
           RoundingMethod: 'Floor'
           OverflowAction: 'Wrap'


y = 

    0.9000

          DataTypeMode: Fixed-point: binary point scaling
            Signedness: Signed
            WordLength: 16
        FractionLength: 15

Use a fixed.Quantizer object to change a binary-point scaled fixed-point fi to a slope-bias scaled fixed-point fi.

x = fi(pi,1,16,13)
q = fixed.Quantizer(numerictype(1,7,1.6,0.2),'Round','Saturate')
y = quantize(q,x)
x = 

    3.1416

          DataTypeMode: Fixed-point: binary point scaling
            Signedness: Signed
            WordLength: 16
        FractionLength: 13

q = 

  fixed.Quantizer with properties:

                   Signed: 1
               WordLength: 7
    SlopeAdjustmentFactor: 1.6000
            FixedExponent: 0
                     Bias: 0.2000
               Signedness: 'Signed'
                    Slope: 1.6000
           FractionLength: 0
           RoundingMethod: 'Round'
           OverflowAction: 'Saturate'


y = 

    3.4000

          DataTypeMode: Fixed-point: slope and bias scaling
            Signedness: Signed
            WordLength: 7
                 Slope: 1.6
                  Bias: 0.2

Input Arguments

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Data type properties to use for quantization, specified as a fixed.Quantizer object.

Data to quantize, specified as a fi object.

Data Types: fi

Version History

Introduced in R2011b

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See Also