我有一个数据框,有两个数字变量fatcontent和saltcontent加上两个因子变量cond和spice描述不同的处理.在该数据框中,对数值变量的每次测量取两次.
a <- data.frame(cond = rep(c("uncooked", "fried", "steamed", "baked", "grilled"),
each = 2, times = 3),
spice = rep(c("none", "chilli", "basil"), each = 10),
fatcontent = c(4, 5, 6828, 7530, 6910, 7132, 5885, 613, 2845, 2867,
25, 18, 2385, 33227, 4233, 4023, 953, 1025, 4465, 5016,
5, 5, 10235, 12545, 5511, 5111, 596, 585, 4012, 3633),
saltcontent = c(2, 5, 4733, 5500, 5724, 15885, 14885, 217, 193, 148,
6, 4, 26738, 24738, 22738, 23738, 267, 256, 1121, 1558,
1, 1, …