plotrix (version 3.7-8)

ablineclip: Add a straight line to a plot

Description

As abline, but has arguments x1,x2,y1,y2 as in clip.

Usage

ablineclip(a=NULL,b=NULL,h=NULL,v=NULL,reg=NULL,coef=NULL,untf=FALSE,
  x1=NULL,x2=NULL,y1=NULL,y2=NULL,...)

Arguments

a

Intercept.

b

Slope.

h

the x-value(s) for vertical line(s).

v

the y-value(s) for horizontal line(s).

reg

Fitted lm object.

coef

Coefficients, typically intercept and slope.

untf

How to plot on log coordinates, see abline.

x1,x2,y1,y2

Clipping limits, see clip.

...

Further arguments passed to abline.

Value

None. Adds to the current plot.

Details

ablineclip sets a new clipping region and then calls abline. If any of the four clipping limits is NULL, the values from par("usr") are substituted. After the call to abline, the old clipping region is restored. In order to make clip work, there is a call to abline that draws a line off the plot.

Multiple lines of the same type can be drawn in a single call, but the clipping region must be the same for each group of lines. Thanks to Berry Boessenkool for pointing this out.

See Also

abline, clip

Examples

# NOT RUN {
 x <- rnorm(100)
 y <- x + rnorm(100)
 lmfit <- lm(y~x)
 plot(x, y, xlim=c(-3.5, 3.5))
 ablineclip(lmfit, x1 = -2, x2 = 2, lty = 2)
 ablineclip(h = 0, x1 = -2,x2 = 2,lty = 3, col = "red")
 ablineclip(v = 0, y1 = -2.5, y2 = 1.5, lty=4, col = "green")
# }