# plot.ru: Plot diagnostics for an ru object In paulnorthrop/rust: Ratio-of-Uniforms Simulation with Transformation

## Description

`plot` method for class "ru". For `d = 1` a histogram of the simulated values is plotted with a the density function superimposed. The density is normalized crudely using the trapezium rule. For `d = 2` a scatter plot of the simulated values is produced with density contours superimposed. For `d > 2` pairwise plots of the simulated values are produced.

## Usage

 ```1 2 3 4 5``` ```## S3 method for class 'ru' plot(x, y, ..., n = ifelse(x\$d == 1, 1001, 101), prob = c(0.1, 0.25, 0.5, 0.75, 0.95, 0.99), ru_scale = FALSE, rows = NULL, xlabs = NULL, ylabs = NULL, points_par = list(col = 8)) ```

## Arguments

 `x` an object of class "ru", a result of a call to `ru`. `y` Not used. `...` Additional arguments passed on to `hist`, `lines`, `contour` or `points`. `n` A numeric scalar. Only relevant if `x\$d = 1` or `x\$d = 2`. The meaning depends on the value of x\$d. For d = 1 : n + 1 is the number of abscissae in the trapezium method used to normalize the density. For d = 2 : an n by n regular grid is used to contour the density. `prob` Numeric vector. Only relevant for d = 2. The contour lines are drawn such that the respective probabilities that the variable lies within the contour are approximately prob. `ru_scale` A logical scalar. Should we plot data and density on the scale used in the ratio-of-uniforms algorithm (TRUE) or on the original scale (FALSE)? `rows` A numeric scalar. When `d` > 2 this sets the number of rows of plots. If the user doesn't provide this then it is set internally. `xlabs, ylabs` Numeric vectors. When `d` > 2 these set the labels on the x and y axes respectively. If the user doesn't provide these then the column names of the simulated data matrix to be plotted are used. `points_par` A list of arguments to pass to `points` to control the appearance of points depicting the simulated values. Only relevant when `d = 2`.

`summary.ru` for summaries of the simulated values and properties of the ratio-of-uniforms algorithm.
 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29``` ```# Log-normal density ---------------- x <- ru(logf = dlnorm, log = TRUE, d = 1, n = 1000, lower = 0, init = 1) ## Not run: plot(x) ## End(Not run) # Improve appearance using arguments to plot() and hist() ## Not run: plot(x, breaks = seq(0, ceiling(max(x\$sim_vals)), by = 0.25), xlim = c(0, 10)) ## End(Not run) # Two-dimensional normal with positive association ---------------- rho <- 0.9 covmat <- matrix(c(1, rho, rho, 1), 2, 2) log_dmvnorm <- function(x, mean = rep(0, d), sigma = diag(d)) { x <- matrix(x, ncol = length(x)) d <- ncol(x) - 0.5 * (x - mean) %*% solve(sigma) %*% t(x - mean) } x <- ru(logf = log_dmvnorm, sigma = covmat, d = 2, n = 1000, init = c(0, 0)) ## Not run: plot(x) ## End(Not run) ```