# x: giorni del febbraio 2012
# y: temperature registrate a Sassello in tali giorni
y <- c(-4.5,   -5, -5.1,-4.2,  -4, -3.9, -4.3, -4.1,-4.1, 
       -4.6, -5.1, -4.7,-3.7,-4.3, -7.6,  -10, -9.3,
      -12.1,-13.3, -9.0,-3.5,-3.8, -7.3,-12.9,-10.2,
       -8.1,-10.2, -6.9,-3.1,  -4, -6.5,-10.8,-12.0,
      -11.6, -7.7, -7.2,-5.4,-5.3,-12.2,-16.7,-19.5,
      -21.9,-21.7,-14.1,  -4,-3.5, -9.0,-16.8,-19.4,
      -20.3,-19.8, -8.0,-4.1,-2.4, -3.5, -2.3, -2.7,
       -4.1, -1.4,    0, 1.2)
x <- seq(1,8+4/8,1/8)
plot(x,y,pch=20)
abline(h=seq(-22,2,2), v=seq(1,9,1/4),lty=3,col="blue")
abline(v=seq(1,9),lty=2)
lines(x,y)