plot.murphydiag_diff: Plotting Murphy diagram difference objects
In aijordan/murphydiagram2: Murphy Diagrams for Forecast Comparisons

Plotting Murphy diagram difference objects

## S3 method for class 'murphydiag_diff'
plot(x, ..., thresholds = 500L, type = "l",
  xlim = NULL, ylim = NULL, main = NULL, xlab = NULL,
  ylab = NULL, level_ci = 0.95, sd_lags = 0)

`x`	an object inheriting from the class `murphydiag_diff`.
`...`	other graphical parameters (see `par`).
`type`	character string (length 1 vector) or vector of 1-character strings indicating the type of plot for each column of `y`, see `plot` for all possible `type`s. The first character of `type` defines the first plot, the second character the second, etc. Characters in `type` are cycled through; e.g., `"pl"` alternately plots points and lines.
`xlim`	the x limits (x1, x2) of the plot. Note that `x1 > x2` is allowed and leads to a ‘reversed axis’. The default value, `NULL`, indicates that the range of the finite values to be plotted should be used.
`ylim`	the y limits of the plot.
`main`	an overall title for the plot: see `title`.
`xlab`	a label for the x axis, defaults to "threshold".
`ylab`	a label for the y axis, defaults to "mean score".
`level_ci`	level for confidence interval (set to `NULL` to omit it)
`sd_lags`	number of autocovariances to use for confidence intervals (defaults to zero; values 1, 2, 3, ... may make sense for time series data. Set to `NULL` for data-driven selection.)