After creating a graph with the following code:
plot(data.exoplanets$loga, data.exoplanets$logMass, ylab="Log of Mass", xlab="Log of Semi Major Axis")
I identified a specific point using:
points(data.exoplanets$loga[1535], data.exoplanets$logMass[1535], col="red", pch=19)
and then added vertical error bars based on KepError:
lines(rep(data.exoplanets$loga[1535],2), c(data.exoplanets$loga[1535]-KepError, data.exoplanets$loga[1535]+KepError), col="red", type="o", pch="_")
Now I am looking to modify this code to include horizontal error bars for the x-axis. Any suggestions?