Plot the linear regression results

ggplotRegression.R

# create function to plot linear regression results
# adapted from https://sejohnston.com/2012/08/09/a-quick-and-easy-function-to-plot-lm-results-in-r/
ggplotRegression <- function (fit) {
  lmdf<- data.frame(fitted_values = fit$fitted.values, actual_values = fit$model[, 1])
  print(names(lmdf))
  ggplot(lmdf, aes(x = actual_values, y = fitted_values)) +
    geom_point() +
    geom_abline(slope = 1, intercept = 0) +
    labs(title = paste("Adj R2 = ", signif(summary(fit)$adj.r.squared, 4),
                       "Intercept =",signif(fit$coef[[1]],5 ),
                       " Slope =",signif(fit$coef[[2]], 5),
                       " P =",signif(summary(fit)$coef[2,4], 5)
                       ),
         x = 'observed value', y = 'predicted value')
}

fit<-lm(Sepal.Length ~ Petal.Width, data = iris)
ggplotRegression(fit)