这是我的数据框df的摘录（完整数据框中有更多的国家和地区）
country.x year emissions etsemit
Austria 2005 16194772.5 16539659
Austria 2005 15039192.4 15275065
Austria 2005 13757090.8 14124646
Austria 2005 13582006.8 14572511
Austria 2009 12526267.6 12767555
Austria 2010 13852187.5 15506112
Austria 2011 13666544.9 15131551
Austria 2012 12256272.5 13121434
Austria 2012 11224625.0 8074514
Austria 2012 9499543.9 6426135
Austria 2015 10623549.8 7514263
Austria 2016 10448925.8 7142937
Belgium 2005 29246990.2 25460856
Belgium 2006 28136794.9 24099282
Belgium 2007 27435552.7 23706084
Belgium 2009 25344134.8 23166180
Belgium 2009 25744709.0 21185552
Belgium 2009 26341043.0 22073616
Belgium 2011 22921875.0 18950876
Belgium 2012 22809482.4 17463388
Belgium 2013 21242431.6 16728267
Belgium 2013 20375966.8 15230243
Belgium 2013 21091058.6 16053800
Belgium 2016 19792162.1 15027777
我想获取每个emissions和country.x的{{1}}之和。结果应该输入到一个新的数据框中，如下所示：
year我正在努力根据 country.x year emissions
Austria 2005 value of calculation SUM
Austria 2009 value of calculation SUM
Austria 2010 value of calculation SUM
Austria 2011 value of calculation SUM
Austria 2012 value of calculation SUM
Austria 2015 value of calculation SUM
Austria 2016 value of calculation SUM
Belgium 2005 value of calculation SUM
Belgium 2006 value of calculation SUM
Belgium 2007 value of calculation SUM
Belgium 2009 value of calculation SUM
Belgium 2011 value of calculation SUM
Belgium 2012 value of calculation SUM
Belgium 2013 value of calculation SUM
Belgium 2016 value of calculation SUM
和`year创建总和。我想这很简单，但是请问我一个问题。
感谢任何类型的帮助。
Nordsee
答案 0 :(得分：2)
基本R：
aggregate(emissions~country.x + year , df, sum)
dplyr：
#install.packages("dplyr")
library(dplyr)
df %>% group_by(country.x, year) %>% summarise(emissions_sum = sum(emissions))