【发布时间】:2016-10-04 22:49:30
【问题描述】:
使用df
date <- c(rep(as.Date("2003-01-05"), 5), rep(as.Date("2004-01-05"), 5), rep(as.Date("2005-01-05"), 5), rep(as.Date("2006-01-05"), 5))
parameter <- rep(c("param_A", "param_B", "param_C", "param_D", "param_E"), 4)
df <- data.frame(date, parameter)
df$year <- year(df$date)
如何将param_A 删除为2003,但保留所有其他年份?
【问题讨论】: