使用for循环一次打开多个包

有人能告诉我为什么这个代码在库中给出错误

错误（包[1]）：“包”的长度必须是1

   packages <- c("googleVis","dplyr","ggvis","openintro","plotly","maps","RColorBrewer","mapproj","stargazer","swirl")

for (i in 1:length(packages)) {
    library(packages[i])
}

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packages找到了答案。只需将character.only=T作为参数添加到库函数中即可。
解决了这个问题。只需将character.only=T作为参数添加到库函数。
library（packages[i]，character.only=T）library（packages[i]，character.only=T）