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Get Information About Fixed-Point System Objects Display Fixed-Point Properties for System Objects |

System objects that support fixed-point data processing have
fixed-point properties, which you can display for a particular object
by typing `dsp.<ObjectName>.helpFixedPoint` at
the command line. See
Display Fixed-Point Properties
for System Objects to set the display
of System object™ fixed-point properties.

The following signal processing System objects support fixed-point data processing.

You can control whether the software displays fixed-point properties with either of the following commands:

`matlab.system.showFixedPointProperties``matlab.system.hideFixedPointProperties`

at the MATLAB^{®} command line. These commands set
the **Show fixed-point properties** display option.
You can also set the display option directly via the MATLAB preferences
dialog box. Click **Preferences** on the MATLAB Toolstrip.
The Preferences dialog box opens. Scroll down and sselect **System
Objects**. Finally, select or deselect **Show
fixed-point properties**.

If an object supports fixed-point data processing, its fixed-point properties are active regardless of whether they are displayed or not.

A number of properties affect the fixed-point data processing used by a System object. Objects perform fixed-point processing and use the current fixed-point property settings when they receive fixed-point input.

You change the values of fixed-point properties in the same
way as you change any System object property value. See Configure Components for Your System.
You also use the Fixed-Point Designer™ `numerictype` object
to specify the desired data type as fixed-point, the signedness, and
the word- and fraction-lengths. System objects support these values
of `DataTypeMode`: `Boolean`, `Double`, `Single`,
and `Fixed-point: binary point scaling`.

In the same way as for blocks, the data type properties of many
System objects can set the appropriate word lengths and scalings automatically
by using full precision. System objects assume that the target specified
on the Configuration Parameters Hardware Implementation target is `ASIC/FPGA`.

If you have not set the property that activates a dependent
property and you attempt to change that dependent property, a warning
message displays. For example, for the `dsp.FFT` object,
before you set `CustomOutputDataType` to `numerictype(1,32,30)` you
must set `OutputDataType` to `'Custom'`.

`FullPrecisionOverride` is a convenience
property that, when you set to `true`, automatically
sets the appropriate properties for an object to use full-precision
to process fixed-point input. For System objects, full precision,
fixed-point operation refers to growing just enough additional bits
to compute the ideal full precision result. This operation has no
minimum or maximum range overflow nor any precision loss due to rounding
or underflow. It is also independent of any hardware-specific settings.
The data types chosen are based only on known data type ranges and
not on actual numeric values. Unlike full precision for `dfilt` objects,
full precision for System objects does not optimize coefficient values.

When you set the `FullPrecisionOverride` property
to `true`, the other fixed-point properties it controls
no longer apply and any of their non-default values are ignored. These
properties are also hidden. To specify individual fixed-point properties,
you must first set `FullPrecisionOverride` to `false`.

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