Given

p <- function(x) {
  if (x == -4) {
    0.1
  } else if (x == -1) {
    0.2
  } else if (x == 1) {
    0.6
  } else if (x == 2) {
    0.1
  } else {
    0
  }
}

How would I plot the PMF and CDF. No distribution is specified so I cant use the build in commands. What would be the best way to plot these

Update

If piece-wise CDF is needed, you can try define cdf function

cdf <- function(x) {
    ifelse(
        x <= -4,
        0,
        ifelse(
            x <= -1,
            0.1,
            ifelse(
                x <= 1,
                0.3,
                ifelse(
                    x < 2,
                    0.9,
                    1
                )
            )
        )
    )
}

and then run

curve(cdf, -5, 5, n = 1e3 + 1)

Previous

Try this for PMF

df <- data.frame(x = c(-4, -1, 1, 2), p = c(.1, .2, .6, .1))
plot(df, type = "l")
points(df)

For CDF, you can try a similar one

plot(df_cdf <- transform(df, p = cumsum(p)), type = "l")
points(df_cdf)