User`s guide

Filtering Data
Tip If you need to change the frequency units from rad/s to Hz,select
Style > Frequency (Hz). To change the frequency units from
Hz to
rad/s, select Style > Frequency (rad/s).
6 In the Range is list, select one of the follo wing:
•
Pass band — Allows data in the selected frequency range.
•
Stop band — Excludes data in the selected frequency range.
7 In the Data name field, enter the name of the data set containing the
selected data.
8 Click Insert. This action saves the sele ction as a new data set and adds
it to the Data Board.
9 To select another range, repeat steps 5 to 8.
How to Filter Data at the Command Line
• “Simple Passband Filter” on page 1-111
• “Defining a Custom Filter” on page 1-112
• “Causal and Noncausal Filters” on page 1-113
Simple Passband Filter
Use id filt to apply passband and other custom filters to a time-domain or
a frequency-domain
iddata object.
In ge nera l, you ca n specify any custom filter. Use this syntax to filter an
iddata object data using the filter called fi lter :
fdata = idfilt(data,filter)
In the simplest case, you can specify a passband filter for time-do main data
using the following syntax:
fdata = idfilt(data,[wl wh])
1-111