Fitting a lognormal in R to a large data set and plotting the Q-Q distribution

lognormal.R

library(MASS)

# generate a million lognormal samples
n <- 1000000
dat <- rlnorm(n, meanlog = 0, sdlog = 1)

# add some noise (optional)
dat <- dat + runif(n, 0, 1)

# create a vector of histogram breaks
x <- seq(0,max(dat),length=700)

# histogram the data
hst <- hist(dat, breaks=x)

# fit a lognormal distribution
fit_params <- fitdistr(dat,"lognormal")

# generate values given our fit parameters
fit <- dlnorm(x, fit_params$estimate['meanlog'], fit_params$estimate['sdlog'])

# plot the fit and original distributions
plot(x, fit, type="l", ylab="Density",
     xlab="X", ylim=c(0,max(hst$density)), xlim=c(0,10))
title(main = "Density histogram with lognormal fit")
lines(hst$mid, hst$density, type="l", col="red")
legend(8,0.15,legend=c("Fit","Data"),lty=c(1,1),col=c("black","red"))


## Q-Q plot

# create a vector of quantiles
quants <-seq(0,1,length=81)[2:80]

# find quantiles for the fitted distribution
fit_quants <- qlnorm(quants,fit_params$estimate['meanlog'], fit_params$estimate['sdlog'])

# find quantiles of the original data
data_quants <- quantile(dat,quants)

# fit and data quantiles side by side
data.frame(fit_quants,data_quants)

# create Q-Q plot
plot(fit_quants, data_quants, xlab="Theoretical Quantiles", ylab="Sample Quantiles")
title(main = "Q-Q plot of lognormal fit against data")
abline(0,1)

When I code my data up to line 27 above and run it, the console portion of Rstudio screen just retypes the entire code...... and does nothing, no errors are reported, but no graph is displayed.....???

this works fine with my RStudio installation. Try running in a terminal R session, or you could try debugging your RStudio install by generating another simple plot