假设我的数据长这样:
有什么建议吗?
2372 Kansas KS2000111 HUMBOLDT, CITY OF ATRAZINE 1.3 05/07/2006
9104 Kansas KS2000111 HUMBOLDT, CITY OF ATRAZINE 0.34 07/23/2006
9212 Kansas KS2000111 HUMBOLDT, CITY OF ATRAZINE 0.33 02/11/2007
2094 Kansas KS2000111 HUMBOLDT, CITY OF ATRAZINE 1.4 05/06/2007
16763 Kansas KS2000111 HUMBOLDT, CITY OF ATRAZINE 0.61 05/11/2009
1076 Kansas KS2000111 HUMBOLDT, CITY OF METOLACHLOR 0.48 05/12/2002
1077 Kansas KS2000111 HUMBOLDT, CITY OF METOLACHLOR 0.3 05/07/2006
我希望能够通过分析物和部分匹配日期(只需要年份)来进行子集操作。我一直在尝试,但是我知道这并不完全正确。
data[data$Analyte=="ATRAZINE" & grep("2006",as.character(data$Date)),]
有什么建议吗?