xgb.copy.Booster: Deep-copies a Booster Object

In xgboost: Extreme Gradient Boosting

Deep-copies a Booster Object

Description

Creates a deep copy of an 'xgb.Booster' object, such that the C object pointer contained will be a different object, and hence functions like xgb.attr() will not affect the object from which it was copied.

Usage

xgb.copy.Booster(model)

Arguments

model

An 'xgb.Booster' object.

Value

A deep copy of model - it will be identical in every way, but C-level functions called on that copy will not affect the model variable.

Examples

library(xgboost)

data(mtcars)

y <- mtcars$mpg
x <- mtcars[, -1]

dm <- xgb.DMatrix(x, label = y, nthread = 1)

model <- xgb.train(
  data = dm,
  params = xgb.params(nthread = 1),
  nrounds = 3
)

# Set an arbitrary attribute kept at the C level
xgb.attr(model, "my_attr") <- 100
print(xgb.attr(model, "my_attr"))

# Just assigning to a new variable will not create
# a deep copy - C object pointer is shared, and in-place
# modifications will affect both objects
model_shallow_copy <- model
xgb.attr(model_shallow_copy, "my_attr") <- 333
# 'model' was also affected by this change:
print(xgb.attr(model, "my_attr"))

model_deep_copy <- xgb.copy.Booster(model)
xgb.attr(model_deep_copy, "my_attr") <- 444
# 'model' was NOT affected by this change
# (keeps previous value that was assigned before)
print(xgb.attr(model, "my_attr"))

# Verify that the new object was actually modified
print(xgb.attr(model_deep_copy, "my_attr"))

xgboost documentation built on Dec. 3, 2025, 5:06 p.m.