データの前処理

平均値、オフセット、線形トレンドの除去、欠損データの復元、データサンプリングレートの変更

関数

`detrend`	Subtract offset or trend from time-domain signals contained in `iddata` objects
`retrend`	Add offsets or trends to time-domain data signals stored in `iddata` objects
`diff`	iddata オブジェクトの差分信号
`idfilt`	Filter data using user-defined passbands, general filters, or Butterworth filters
`misdata`	Reconstruct missing input and output data
`nkshift`	Shift data sequences
`idresamp`	Resample time-domain data by decimation or interpolation
`idresampOptions`	Option set for `idresamp` (R2023a 以降)
`resample`	(Not recommended) Resample time-domain data that is stored in an `iddata` object by decimation or interpolation (requires Signal Processing Toolbox software)
`getTrend`	Create trend information object to store offset, mean, and trend information for time-domain signals stored in `iddata` object
`chgFreqUnit`	周波数応答データモデルの周波数単位の変更
`fdel`	周波数応答データ (FRD) モデルから指定したデータを削除
`TrendInfo`	Offset and linear trend slope values for detrending data

Preprocess Data Using Quick Start
Subtract mean values from data, and specify estimation and validation data.
特定のデータセグメントの抽出とモデル化
この例では、精度が高いデータセグメントだけをマージして残りは無視することで複数実験の時間領域データセットを作成する方法を示します。
How to Detrend Data Using the App
Before you can perform this task, you must have regularly-sampled, steady-state time-domain data imported into the System Identification app. See Import Time-Domain Data into the App). For transient data, see How to Detrend Data at the Command Line.
How to Detrend Data at the Command Line
Before you can perform this task, you must have time-domain data as an iddata object. See Representing Time- and Frequency-Domain Data Using iddata Objects.
Resampling Data Using the App
Use the System Identification app to resample time-domain data. To specify additional options, such as the prefilter order, see Resampling Data at the Command Line.
Resampling Data at the Command Line
Decimate and interpolate time-domain data.
How to Filter Data Using the App
The System Identification app lets you filter time-domain data using a fifth-order Butterworth filter by enhancing or selecting specific passbands.
How to Filter Data at the Command Line
Use idfilt to apply passband and other custom filters to a time-domain or a frequency-domain iddata object.

Handling Missing Data and Outliers
Handling missing or erroneous data values.
Handling Offsets and Trends in Data
Removing and restoring constant offsets and linear trends in data signals.
Resampling Data
Decimating and interpolating (resampling) data.
Filtering Data
Deciding whether to filter data before model estimation and how to prefilter data.