R 報錯： x invalid 'type' (character) of argument

運行 R 代碼時 figa1= figa %>% group_by(ind) %>% summarize(sum = sum(count)) 提示報錯信息：

Error: Problem with summarise() column sum.
i sum = sum(count).
x invalid 'type' (character) of argument
i The error occurred in group 1: ind = >=4.

使用命令 class(figa$count) ：

[1] "character"

發現是因為count列為字符型，而sum函數要求數值型，因此只需要將count轉為數值型即可：

figa1= figa %>% mutate(count = as.numeric(as.character(count))) %>% group_by(ind) %>% summarize(total = sum(count))

mutate(count = as.numeric(as.character(count)))指的是把count轉為數值型