# hexVP.abline

##### Add a Straight Line to a HexPlot

This function adds one or more straight lines through the current
plot; it is the hexbin version of `abline()`

.

- Keywords
- aplot

##### Usage

```
hexVP.abline(hvp, a = NULL, b = NULL, h = numeric(0), v = numeric(0),
col = "black", lty = 1, lwd = 2, …)
```

##### Arguments

- hvp
A hexViewport object that is currently on the active device

- a,b
the intercept and slope or if

`b`

is`NULL`

, an`lm`

object or a vector of length 2 with`c(intercept,slope)`

- h
the y-value for a horizontal line.

- v
the x-value for a vertical line.

- col, lty, lwd
line color, type and width.

- …
further graphical parameters.

##### Details

The first form specifies the line in intercept/slope form
(alternatively `a`

can be specified on its own and is taken to
contain the slope and intercept in vector form).

The `h=`

and `v=`

forms draw horizontal and vertical
lines at the specified coordinates.

The `coef`

form specifies the line by a vector containing the
slope and intercept.

`lm`

is a regression object which contains `reg$coef`

. If it is
of length 1 then the value is taken to be the slope of a line
through the origin, otherwise, the first 2 values are taken to be
the intercept and slope.

##### See Also

*Documentation reproduced from package hexbin, version 1.27.1, License: GPL-2*