我有一个数据集,看起来像下面这样。实际的数据集中有8619行。
Athlete Competing Country Year Total Medals
Michael Phelps United States 2012 6
Alicia Coutts Australia 2012 5
Missy Franklin United States 2012 5
Brian Leetch United States 2002 1
Mario Lemieux Canada 2002 1
Ylva Lindberg Sweden 2002 1
Eric Lindros Canada 2002 1
Ulrica Lindström Sweden 2002 1
Shelley Looney United States 2002 1
我希望按照国家、年份和奖牌总数重新排列这些数据。
我想要的结果是:
Country Year SumOfMedals
United States 2012 11
United States 2002 2
...
by(newmd$Total.Medals, newmd$Year, FUN=sum)
by(md$Total.Medals, md$Competing.Country, FUN=sum)
我尝试使用参数,但仍然卡住了。 有人能帮助我吗?
aggregate(Total.Medals ~ Competing.Country + Year, md, sum)
。 - Ritchie Sacramento