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Construct unsigned fixed-point numeric object

`a = ufi`

a = ufi(v)

a = ufi(v,w)

a = ufi(v,w,f)

a = ufi(v,w,slope,bias)

a = ufi(v,w,slopeadjustmentfactor,fixedexponent,bias)

You can use the `ufi`

constructor function
in the following ways:

`a = ufi`

is the default constructor and returns an unsigned`fi`

object with no value, 16-bit word length, and 15-bit fraction length.`a = ufi(v)`

returns an unsigned fixed-point object with value`v`

, 16-bit word length, and best-precision fraction length.`a = ufi(v,w)`

returns an unsigned fixed-point object with value`v`

, word length`w`

, and best-precision fraction length.`a = ufi(v,w,f)`

returns an unsigned fixed-point object with value`v`

, word length`w`

, and fraction length`f`

.`a = ufi(v,w,slope,bias)`

returns an unsigned fixed-point object with value`v`

, word length`w`

,`slope`

, and`bias`

.`a = ufi(v,w,slopeadjustmentfactor,fixedexponent,bias)`

returns an unsigned fixed-point object with value`v`

, word length`w`

,`slopeadjustmentfactor`

,`fixedexponent`

, and`bias`

.

`fi`

objects created by the `ufi`

constructor
function have the following general types of properties:

These properties are described in detail in fi Object Properties in the Properties Reference.

`fi`

objects created by the `ufi`

constructor
function have no local fimath.

The data properties of a `fi`

object are always
writable.

`bin`

— Stored integer value of a`fi`

object in binary`data`

— Numerical real-world value of a`fi`

object`dec`

— Stored integer value of a`fi`

object in decimal`double`

— Real-world value of a`fi`

object, stored as a MATLAB^{®}`double`

`hex`

— Stored integer value of a`fi`

object in hexadecimal`int`

— Stored integer value of a`fi`

object, stored in a built-in MATLAB integer data type. You can also use`int8`

,`int16`

,`int32`

,`int64`

,`uint8`

,`uint16`

,`uint32`

, and`uint64`

to get the stored integer value of a`fi`

object in these formats`oct`

— Stored integer value of a`fi`

object in octal

These properties are described in detail in fi Object Properties.

When you create a `fi`

object with the `ufi`

constructor
function, that `fi`

object does not have a local `fimath`

object.
You can attach a `fimath`

object to that `fi`

object
if you do not want to use the default fimath settings. For more information,
see fimath Object Construction in the Fixed-Point
Designer™ documentation.

`fimath`

— fixed-point math object

The following `fimath`

properties are always
writable and, by transitivity, are also properties of a `fi`

object.

`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`

.`OverflowAction`

— Action to take on overflow`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`RoundingMethod`

— Rounding method`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`

— The word length, in bits, of the sum data type

These properties are described in detail in fimath Object Properties.

When you create a `fi`

object, a `numerictype`

object
is also automatically created as a property of the `fi`

object.

`numerictype`

— Object containing all
the data type information of a `fi`

object, Simulink^{®} signal
or model parameter

The following `numerictype`

properties are,
by transitivity, also properties of a `fi`

object.
The properties of the `numerictype`

object become
read only after you create the `fi`

object. However,
you can create a copy of a `fi`

object with new values
specified for the `numerictype`

properties.

`Bias`

— Bias of a`fi`

object`DataType`

— Data type category associated with a`fi`

object`DataTypeMode`

— Data type and scaling mode of a`fi`

object`FixedExponent`

— Fixed-point exponent associated with a`fi`

object`SlopeAdjustmentFactor`

— Slope adjustment associated with a`fi`

object`FractionLength`

— Fraction length of the stored integer value of a`fi`

object in bits`Scaling`

— Fixed-point scaling mode of a`fi`

object`Signed`

— Whether a`fi`

object is signed or unsigned`Signedness`

— Whether a`fi`

object is signed or unsigned### Note

`numerictype`

objects can have a`Signedness`

of`Auto`

, but all`fi`

objects must be`Signed`

or`Unsigned`

. If a`numerictype`

object with`Auto`

`Signedness`

is used to create a`fi`

object, the`Signedness`

property of the`fi`

object automatically defaults to`Signed`

.`Slope`

— Slope associated with a`fi`

object`WordLength`

— Word length of the stored integer value of a`fi`

object in bits

For further details on these properties, see numerictype Object Properties.

For information about the display format of `fi`

objects,
refer to View Fixed-Point Data.

For examples of casting, see Cast fi Objects.

For example, the following creates an unsigned `fi`

object
with a value of `pi`

, a word length of 8 bits, and
a fraction length of 3 bits:

a = ufi(pi,8,3) a = 3.1250 DataTypeMode: Fixed-point: binary point scaling Signedness: Unsigned WordLength: 8 FractionLength: 3

Default `fimath`

properties are associated
with `a`

. When a `fi`

object does
not have a local `fimath`

object, no `fimath`

object
properties are displayed in its output. To determine whether a `fi`

object
has a local `fimath`

object, use the `isfimathlocal`

function.

isfimathlocal(a) ans = 0

A returned value of `0`

means the `fi`

object
does not have a local `fimath`

object. When the `isfimathlocal`

function
returns a `1`

, the `fi`

object has
a local `fimath`

object.

The value `v`

can also be an array:

a = ufi((magic(3)/10),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 Signedness: Unsigned WordLength: 16 FractionLength: 12 >>

If you omit the argument `f`

, it is set automatically
to the best precision possible:

a = ufi(pi,8) a = 3.1406 DataTypeMode: Fixed-point: binary point scaling Signedness: Unsigned WordLength: 8 FractionLength: 6

If you omit `w`

and `f`

, they
are set automatically to 16 bits and the best precision possible,
respectively:

a = ufi(pi) a = 3.1416 DataTypeMode: Fixed-point: binary point scaling Signedness: Unsigned WordLength: 16 FractionLength: 14

`fi`

| `fimath`

| `fipref`

| `isfimathlocal`

| `numerictype`

| `quantizer`

| `sfi`