fi - Construct fi object

Syntax

a = fi
a = fi(v)
a = fi(v,s)
a = fi(v,s,w)
a = fi(v,s,w,f)
a = fi(v,s,w,slope,bias)
a = fi(v,s,w,slopeadjustmentfactor,fixedexponent,bias)
a = fi(v,T)
a = fi(v,F)
b = fi(a,F)
a = fi(v,T,F)
a = fi(v,s,F)
a = fi(v,s,w,F)
a = fi(v,s,w,f,F)
a = fi(v,s,w,slope,bias,F)
a = fi(v,s,w,slopeadjustmentfactor,fixedexponent,bias,F)
a = fi(...'PropertyName',PropertyValue...)
a = fi('PropertyName',PropertyValue...)

Description

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

The fi object has the following three general types of properties:

Data Properties

The data properties of a fi object are always writable.

These properties are described in detail in fi Object Properties.

fimath Properties

When you create a fi object, a fimath object is also automatically created as a property of the fi object.

The following fimath properties are, by transitivity, also properties of a fi object. The properties of the fimath object listed below are always writable.

These properties are described in detail in fimath Object Properties.

numerictype Properties

When you create a fi object, a numerictype object is also automatically created as a property of the fi object.

The following numerictype properties are, by transitivity, also properties of a fi object. The properties of the numerictype object listed below are not writable once the fi object has been created. However, you can create a copy of a fi object with new values specified for the numerictype properties.

These properties are described in detail in numerictype Object Properties.

Examples

Example 1

For example, the following creates a fi object with a value of pi, a word length of 8 bits, and a fraction length of 3 bits:

a = fi(pi, 1, 8, 3) 

a =
 
    3.1250

          DataTypeMode: Fixed-point: binary point scaling
                Signed: true
            WordLength: 8
        FractionLength: 3

Example 2

The value v can also be an array:

a = fi((magic(3)/10), 1, 16, 12) 

a =
 
    0.8000    0.1001    0.6001
    0.3000    0.5000    0.7000
    0.3999    0.8999    0.2000

          DataTypeMode: Fixed-point: binary point scaling
                Signed: true
            WordLength: 16
        FractionLength: 12

Example 3

If you omit the argument f, it is set automatically to the best precision possible:

 a = fi(pi, 1, 8) 

a =
 
    3.1563

          DataTypeMode: Fixed-point: binary point scaling
                Signed: true
            WordLength: 8
        FractionLength: 5

Example 4

If you omit w and f, they are set automatically to 16 bits and the best precision possible, respectively:

a = fi(pi, 1) 

a =
 
    3.1416

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

Example 5

You can use property name/property value pairs to set fi properties when you create the object:

a = fi(pi, 'roundmode', 'floor', 'overflowmode', 'wrap') 

a =
 
    3.1415

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

See Also

fimath, fipref, numerictype, quantizer

  


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