[R] Plot dataframe with color based on a column value

[Luigi Marongiu]

Hello
is it possible to color the data of a dataframe according to the
values of one column?
I have a dataframe that OI have subdivided into X and Y, with a third
Z with the sample number. I would like to plot Y~X but coloring using
Z. But I would like to use base R and not lines.
Is that possible?
Thank you

```
d <- 2
K <- 10^13
A1_0 <- 1
A2_0 <- 100
A3_0 <- 500
A4_0 <- 10000
PCR <- function(initCopy, dupRate, Carry) {
  ROI_T = initCopy
  A = array()
  for (i in 1:45) {
    ROI_TplusOne <- ROI_T * dupRate * (1 - ROI_T/Carry)
    A[i] <- ROI_TplusOne
    ROI_T <- ROI_TplusOne
  }
  return(A)
}
A1 <- PCR(A1_0, d, K)
A2 <- PCR(A2_0, d, K)
A3 <- PCR(A3_0, d, K)
A4 <- PCR(A4_0, d, K)
# store results and plot
Z <- c(rep(1, 45), rep(2, 45), rep(3, 45), rep(4, 45))
X = rep(1:45,4)
Y = c(A1, A2, A3, A4)
ROI <- data.frame(Z, X, Y)
plot(Y ~ X, data = ROI, type = "l", lwd = 3)
```