result
result <- c(0, seq(from = -1, by = 2.5, length.out = 4), 7:8)
c(0, -1, 1.5, 4, 7, 8)
c(0, -1, 1.5, 4, 6.5, 7, 8)
c(0, -1, 2.5, 5, 7.5, 7, 8)
c(0, -1, 1.5, 4, 6.5, 8, 7)