Offset and linear trend slope values for detrending data

`TrendInfo`

class represents offset and linear
trend information of input and output data. Constructing the corresponding
object lets you:

Compute and store mean values or best-fit linear trends of input and output data signals.

Define specific offsets and trends to be removed from input-output data.

By storing offset and trend information, you can apply it to multiple data sets.

After estimating a linear model from detrended data, you can
simulate the model at original operation conditions by adding the
saved trend to the simulated output using `retrend`

.

For transient data, if you want to define a specific offset
or trend to be removed from this data, create the `TrendInfo`

object
using `getTrend`

. For example:

T = getTrend(data)

where data is the `iddata`

object from which
you will be removing the offset or linear trend, and `T`

is
the `TrendInfo`

object. You must then assign specific
offset and slope values as properties of this object before passing
the object as an argument to `detrend`

.

For steady-state data, if you want to detrend the data and store
the trend information, use the `detrend`

command
with the output argument for storing trend information.

After creating the object, you can use `get`

or
dot notation to access the object property values.

Property Name | Default | Description |
---|---|---|

`DataName` | `''` | Name of the `iddata` object from which trend
information is derived (if any) |

`InputOffset` | `zeros(1,nu)` , where `nu` is
the number of inputs | For transient data, the physical equilibrium offset you specify for each input signal. For steady-state data, the mean of input values. Computed automatically when detrending the data. If removing a linear trend from the input-output data, the value of the line at `t0` , where`t0` is the start time.
For multiple experiment data, this is a cell array of size equal to the number of experiments in the data set. |

`InputSlope` | `zeros(1,nu)` , where `nu` is
the number of inputs | Slope of linear trend in input data, computed automatically
when using the For multiple experiment data, this is a cell array of size equal to the number of experiments in the data set. |

`OutputOffset` | `zeros(1,ny)` , where `ny` is
the number of outputs | For transient data, the physical equilibrium offset you specify for each output signal For steady-state data, the mean of output values. Computed automatically when detrending the data. If removing a linear trend from the input-output data, the value of the line at `t0` , where`t0` is the start time.
For multiple experiment data, this is a cell array of size equal to the number of experiments in the data set. |

`OutputSlope` | `zeros(1,ny)` , where `ny` is
the number of outputs | Slope of linear trend in output data, computed automatically
when using the |

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