# xgb.gblinear.history

##### Extract gblinear coefficients history.

A helper function to extract the matrix of linear coefficients' history
from a gblinear model created while using the `cb.gblinear.history()`

callback.

##### Usage

`xgb.gblinear.history(model, class_index = NULL)`

##### Arguments

- model
either an

`xgb.Booster`

or a result of`xgb.cv()`

, trained using the`cb.gblinear.history()`

callback.- class_index
zero-based class index to extract the coefficients for only that specific class in a multinomial multiclass model. When it is NULL, all the coeffients are returned. Has no effect in non-multiclass models.

##### Value

For an `xgb.train`

result, a matrix (either dense or sparse) with the columns
corresponding to iteration's coefficients (in the order as `xgb.dump()`

would
return) and the rows corresponding to boosting iterations.

For an `xgb.cv`

result, a list of such matrices is returned with the elements
corresponding to CV folds.

*Documentation reproduced from package xgboost, version 0.82.1, License: Apache License (== 2.0) | file LICENSE*