xgboost重要性繪圖（ggplot）在R

Question

我已經繪製了xgboosot中的重要性矩陣，我想讓文字變大，我該怎麼做？

gg <- xgb.ggplot.importance(importance_matrix = a,top_n = 15) 

Answer 1

使用theme()增加字體大小。

下面我給出了一個最小可重現的例子;

# Load library 
library(ggplot2) 
require(xgboost) 
# load data 
data(agaricus.train, package='xgboost') 
data(agaricus.test, package='xgboost') 
train <- agaricus.train 
test <- agaricus.test 
# create model 
bst <- xgboost(data = train$data, label = train$label, max.depth = 2, 
       eta = 1, nthread = 2, nround = 2, objective = "binary:logistic") 
# importance matrix 
imp_matrix <- xgb.importance(colnames(agaricus.train$data), model = bst) 
# plot 
xgb.ggplt<-xgb.ggplot.importance(importance_matrix = imp_matrix, top_n = 4) 
# increase the font size for x and y axis 
xgb.ggplt+theme(text = element_text(size = 20), 
    axis.text.x = element_text(size = 15, angle = 45, hjust = 1)) 

使用？主題，看看你可以修改參數列表。