addInterval {plotfunctions}

Draw intervals or arrows on plots.

Description

Add horizontal or vertical interval indications. This function can also be used to plot asymmetric (non-parametric) error bars or confidence intervals. Basically a wrapper around arrows.

Usage

addInterval(
  pos,
  lowVals,
  highVals,
  horiz = TRUE,
  minmax = NULL,
  length = 0.05,
  ...
)

Arguments

pos

Vector with x- or y-values (depending on horizontal).

lowVals

Vector with low values, .

highVals

Vector with errors or confidence bands.

horiz

Logical: whether or not to plot the intervals horizontally. Defaults to TRUE (horizontal intervals).

minmax

Optional argument, vector with two values indicating the minimum and maximum value for the error bars. If NULL (default) the error bars are not corrected.

length

Number, size of the edges in inches.

...

Optional graphical parameters (see par) to be forwarded to the function arrows.

Author(s)

Jacolien van Rij

See Also

Other Functions for plotting: add_bars(), add_n_points(), alphaPalette(), alpha(), check_normaldist(), color_contour(), dotplot_error(), drawDevArrows(), emptyPlot(), errorBars(), fill_area(), getCoords(), getFigCoords(), getProps(), gradientLegend(), legend_margin(), marginDensityPlot(), plot_error(), plot_image(), plotsurface(), sortBoxplot()

Examples

emptyPlot(1000,5, xlab='Time', ylab='Y')
# add interval indication for Time=200 to Time=750:
addInterval(1, 200, 750, lwd=2, col='red')

# zero-length intervals also should work:
addInterval(pos=521, lowVals=c(1.35, 1.5, 4.33), highVals=c(1.15,1.5, 4.05),
    horiz=FALSE, length=.1, lwd=4)

# combine with getCoords for consistent positions with different axes:
par(mfrow=c(2,2))
# 1st plot:
emptyPlot(1000,c(-1,5), h0=0)
addInterval(getCoords(.1,side=2), 200,800, 
    col='red', lwd=2)
addInterval(getCoords(.5,side=1), 1,4, horiz=FALSE,
    col='blue', length=.15, angle=100, lwd=4)
abline(h=getCoords(.1, side=2), lty=3, col='red', xpd=TRUE)
abline(v=getCoords(.5, side=1), lty=3, col='blue', xpd=TRUE)
# 2nd plot:
emptyPlot(1000,c(-250, 120), h0=0)
addInterval(getCoords(.1,side=2), 750,1200, 
    col='red', lwd=2, minmax=c(0,1000))
abline(h=getCoords(.1, side=2), lty=3, col='red', xpd=TRUE)
# 3rd plot:
emptyPlot(c(-50,50),c(20,120), h0=0)
addInterval(getCoords(.5,side=1), 80,120, horiz=FALSE,
    col='blue', code=2, length=.15, lwd=4, lend=1)
abline(v=getCoords(.5, side=1), lty=3, col='blue', xpd=TRUE)

# Alternative boxplots: 
b <- boxplot(count ~ spray, data = InsectSprays, plot=FALSE)$stats
emptyPlot(c(1,6), range(b[c(1,5),]), h0=0)
addInterval(1:6, b[1,], b[5,], horiz=FALSE)
# no end lines:
addInterval(1:6, b[2,], b[4,], horiz=FALSE, lwd=8, length=0, lend=2)
# no error with zero-length intervals:
addInterval(1:6, b[3,], b[3,], horiz=FALSE, lwd=2, length=.1, lend=2)

# reset
par(mfrow=c(1,1))