# conspire

##### Plot Together According to a Formula

Given a data frame and a formula involving variables in the data frame, plot the left hand side of the formula versus the right hand side.

- Keywords
- spatial

##### Usage

`conspire(indata, formula, subset=NULL, lty=NULL, col=NULL)`

##### Arguments

- indata
- A data frame, containing the variables to be plotted or variables from which the plotting coordinates can be computed.
- formula
- an S language formula determining which variables or expressions are plotted.
- subset
- (optional) subset of rows of the data frame that will be plotted.
- lty
- (optional) numeric vector of values of the graphical parameter
`lty`

controlling the line style of each plot. - col
- (optional) numeric vector of values of the graphical parameter
`col`

controlling the colour of each plot.

##### Details

This function is like `plot.formula`

but offers
some extra functionality.
The left and right hand sides of the formula argument
are evaluated in the data frame `indata`

,
and the results are plotted against each other
(the left side on the $y$ axis
against the right side on the $x$ axis).
Both left and right sides may be variables in the data frame
or expressions in these variables.

Multiple curves may be specified by a single formula
of the form
`cbind(y1,y2,...,yn) ~ x`

, where `x,y1,y2,...,yn`

are
expressions involving the variables in the data frame.
Each of the variables `y1,y2,...,yn`

in turn will be plotted
against `x`

.
See the examples.

##### Value

- none. Side effect is a plot.

##### Examples

```
library(spatstat)
df <- data.frame(x=1:20, y=sqrt(1:20), z = sqrt(1:20) + runif(20))
conspire(df, y ~ x) # plots y against x
conspire(df, log(y) ~ log(x)) # plots log(y) against log(x)
conspire(df, z - sqrt(x) ~ x) # plots z - sqrt(x) against x
conspire(df, cbind(y,z) ~ x) # plots y against x AND z against x
conspire(df, cbind(z,sqrt(x)) ~ x)
# plots z against x AND sqrt(x) against x
conspire(df, cbind(z - sqrt(x),0) ~ x)
# plots z - sqrt(x) against x
# with dashed horizontal line at height 0
conspire(df, cbind(y,z) ~ x, col=c(2,3))
# plots y against x in colour 2
# and z against x in colour 3
conspire(df, y ~ x, subset=quote(x < 10))
# plots y against x for x < 10
```

*Documentation reproduced from package spatstat, version 1.0-1, License: GPL version 2 or newer*