分析数据

确定延迟、反馈和激励水平等数据特征

函数

`bode`	动态系统的波特频率响应
`bodemag`	频率响应的仅幅度波特图
`idplot`	Plot input and output channels of estimation data (自 R2023a 起)
`advice`	Analysis and recommendations for data or estimated linear models
`delayest`	根据数据估计时间延迟（死区时间）
`isreal`	Determine whether model parameters or data values are real
`realdata`	Determine whether `iddata` is based on real-valued signals
`checkFeedback`	Identify possible feedback data (自 R2023a 起)
`pexcit`	Level of excitation of input signals
`impulseest`	Nonparametric impulse response estimation
`etfe`	Estimate empirical transfer functions and periodograms
`spa`	Estimate frequency response with fixed frequency resolution using spectral analysis
`spafdr`	Estimate frequency response and spectrum using spectral analysis with frequency-dependent resolution
`dataPlotOptions`	Option set for `idplot` when plotting input/output estimation data contained in a timetable, numeric matrices, or an `iddata` object (自 R2023a 起)

Is Your Data Ready for Modeling?
Before you start estimating models from data, you should check your data for the presence of any undesirable characteristics.
How to Plot Data in the App
After importing data into the System Identification app, as described in 表示数据, you can plot the data.
How to Plot Data at the Command Line
The following table summarizes the commands available for plotting time-domain, frequency-domain, and frequency-response data.
How to Analyze Data Using the advice Command
You can use the advice command to analyze time- or frequency- domain data before estimating a model.
Identify Delay Using Transient-Response Plots
You can use transient-response plots to estimate the input delay, or dead time, of linear systems.