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## View Fixed-Point Data

In Fixed-Point Designer™ software, the fipref object determines the display properties of fi objects. Code examples generally show fi objects as they appear with the following fipref object properties:

• NumberDisplay'RealWorldValue'

• NumericTypeDisplay'full'

• FimathDisplay'full'

Setting 'FimathDisplay' to 'full' provides a quick and easy way to differentiate between fi objects with a local fimath and those that are associated with the default fimath. When 'FimathDisplay' is set to 'full', MATLAB® displays fimath object properties for fi objects with a local fimath. MATLAB never displays fimath object properties for fi objects that are associated with the default fimath. Because of this display difference, you can tell when a fi object is associated with the default fimath just by looking at the output.

Additionally, unless otherwise specified, examples throughout the Fixed-Point Designer documentation use the following default configuration of fimath:

```        RoundingMethod: Nearest
OverflowAction: Saturate
ProductMode: FullPrecision
SumMode: FullPrecision
```

For more information on display settings, refer to fi Object Display Preferences Using fipref.

### Displaying the fimath Properties of fi Objects

To see the output as it appears in most Fixed-Point Designer code examples, set your fipref properties as follows and create two fi objects:

```p = fipref('NumberDisplay', 'RealWorldValue',...
'NumericTypeDisplay', 'full', 'FimathDisplay', 'full');
a = fi(pi,'RoundingMethod', 'Floor', 'OverflowAction', 'Wrap')
b = fi(pi)
```

MATLAB returns the following:

```a =
3.1415

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

RoundingMethod: Floor
OverflowAction: Wrap
ProductMode: FullPrecision
SumMode: FullPrecision

b =
3.1416

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

MATLAB displays fimath object properties in the output of fi object a because a has a local fimath.

MATLAB does not display any fimath object properties in the output of fi object b because b associates itself with the default fimath.

### Hiding the fimath Properties of fi Objects

If you are working with multiple fi objects that have local fimaths, you may want to turn off the fimath object display:

• NumberDisplay'RealWorldValue'

• NumericTypeDisplay'full'

• FimathDisplay'none'

For example,

```p = fipref('NumberDisplay','RealWorldValue',...
'NumericTypeDisplay','full','FimathDisplay','none')

p =

NumberDisplay: 'RealWorldValue'
NumericTypeDisplay: 'full'
FimathDisplay: 'none'
LoggingMode: 'Off'
DataTypeOverride: 'ForceOff'

F = fimath('RoundingMethod','Floor','OverflowAction','Wrap');
a = fi(pi, F)

a =
3.1415

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

Although this setting helps decrease the amount of output produced, it also makes it impossible to tell from the output whether a fi object uses the default fimath. To do so, you can use the isfimathlocal function. For example,

```isfimathlocal(a)

ans =
1```

When the isfimathlocal function returns 1, the fi object has a local fimath. If the function returns 0, the fi object uses the default fimath.

### Shortening the numerictype Display of fi Objects

To reduce the amount of output even further, you can set the NumericTypeDisplay to 'short'. For example,

```p = fipref('NumberDisplay','RealWorldValue',...
'NumericTypeDisplay','short','FimathDisplay','full');

a = fi(pi)

a =
3.1416
s16,13```