首先，将 % 字符串转换为数值:

First, transform the % strings to numeric values:

df[2] <- as.numeric(gsub("%", "", as.character(df[ , 2])))

计算每个Quarter的平均GrossMargin:

dat <- aggregate(GrossMargin ~ Quarter, df, mean)

剧情:

plot(as.factor(dat$Quarter), dat$GrossMargin)

这个答案最初是为了回复这个问题而发布的.

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