multLines function

Plot Multiple Lines

Plots multiple lines based on a vector x and a matrix y, draws thin vertical lines connecting limits represented by columns of y beyond the first. It is assumed that either (1) the second and third columns of y represent lower and upper confidence limits, or that (2) there is an even number of columns beyond the first and these represent ascending quantiles that are symmetrically arranged around 0.5. If options(grType='plotly') is in effect, uses plotly graphics instead of grid or base graphics. For plotly you may want to set the list of possible colors, etc. using pobj=plot_ly(colors=...). lwd,lty,lwd.vert

are ignored under plotly.

multLines(x, y, pos = c('left', 'right'), col='gray',
          lwd=1, lty=1, lwd.vert = .85, lty.vert = 1,
          alpha = 0.4, grid = FALSE,
          pobj=plotly::plot_ly(), xlim, name=colnames(y)[1], legendgroup=name,
          showlegend=TRUE, ...)

Arguments

• x: a numeric vector
• y: a numeric matrix with number of rows equal to the number of x elements
• pos: when pos='left' the vertical lines are drawn, right to left, to the left of the point (x, y[,1). Otherwise lines are drawn left to right to the right of the point.
• col: a color used to connect (x, y[,1]) pairs. The same color but with transparency given by the alpha argument is used to draw the vertical lines
• lwd: line width for main lines
• lty: line types for main lines
• lwd.vert: line width for vertical lines
• lty.vert: line type for vertical lines
• alpha: transparency
• grid: set to TRUE when using grid/lattice
• pobj: an already started plotly object to add to
• xlim: global x-axis limits (required if using plotly)
• name: trace name if using plotly
• legendgroup: legend group name if using plotly
• showlegend: whether or not to show traces in legend, if using plotly
• ...: passed to add_lines or add_segments if using plotly

Author(s)

Frank Harrell

Examples

if (requireNamespace("plotly")) {
  x <- 1:4
  y <- cbind(x, x-3, x-2, x-1, x+1, x+2, x+3)
  plot(NA, NA, xlim=c(1,4), ylim=c(-2, 7))
  multLines(x, y, col='blue')
  multLines(x, y, col='red', pos='right')
}