我试图结合gbm.plot.fit不同plot.gbm的gbm模型。这是我的示例代码：
#----------------------ask on stackexchange----------------------------#
mydata <- read.csv("http://www.ats.ucla.edu/stat/data/binary.csv")
library(gbm)
library(dismo)
full.model<- gbm.step(data=mydata,gbm.x = 2:4,gbm.y = 1,family = "bernoulli", tree.complexity = 5,learning.rate = 0.005, bag.fraction = 0.5)
fit1 <- gbm.step(data=mydata,gbm.x = 2,gbm.y = 1,family = "bernoulli", tree.complexity = 5,learning.rate = 0.005, bag.fraction = 0.5)
a=gbm.plot.fits(full.model,v="gre")
b=plot.gbm(full.model,i.var="gre")
c=gbm.plot.fits(fit1)
d=plot.gbm(fit1)
grid.arrange(a, b, c, d, ncol=2, nrow =2)
错误信息是：
安排Grob（...，as.table = as.table，clip = clip，main = main，：输入必须是grobs！
有人可以告诉我我的代码可能出了什么问题吗？