User`s guide

5 Exporting F ilter Coefficients from FDATool
Choosing the Exp
ort Data Type
The export proce
ssprovidestwowaysyoucanspecifythedatatypetouse
to represent the
filter coefficients. Select one of the options shown in the
following table
when you export your fi lter.
Specify Data Type for
Export
Description
Export suggested
Uses the data type that FDATool suggests to
preserve the fidelity of the filter coef ficients
and the performance of your filter in the
project
Export as
Lets you specify the data type to use to
export the filter coefficients
FDATool exports filter coefficients that use the following data types directly
without modifications:
• Signed integer (8, 16, o r 32 bits)
• Unsigned in teger (8, 16, or 32 bits)
• Double-precision floating point (64 bits)
• Single-precision floating point (32 bits)
Filters in F DA Too l in the Signal Processing Toolbox software use
double-precision floating point. You cannot change the data type.
If you have installed Filter Design Toolbox™ software, you can use the
filter quantization options in FD ATool to set the w ord and fraction lengths
that represent your filter coefficients. F or information abo ut using the
quantization options, refer to Filter Design and Analys is Tool in the Filter
Design Toolbox documentation in the Online help system.
If your filter uses one of the supported data types, Export suggested
specifies that data type.
If your filter does not use one of the supported data types, FDATo ol conver ts
the unsupported data type to one of the supported types and then suggests
that data type. For more information about how FDATool determines the data
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