# envelope.envelope

##### Recompute Envelopes

Given a simulation envelope (object of class `"envelope"`

),
compute another envelope from the same simulation data
using different parameters.

##### Usage

```
# S3 method for envelope
envelope(Y, fun = NULL, ...,
transform=NULL, global=FALSE, VARIANCE=FALSE)
```

##### Arguments

- Y
A simulation envelope (object of class

`"envelope"`

).- fun
Optional. Summary function to be applied to the simulated point patterns.

- …,transform,global,VARIANCE
Parameters controlling the type of envelope that is re-computed. See

`envelope`

.

##### Details

This function can be used to re-compute a simulation envelope from previously simulated data, using different parameter settings for the envelope: for example, a different significance level, or a global envelope instead of a pointwise envelope.

The function `envelope`

is generic. This is the method for
the class `"envelope"`

.

The argument `Y`

should be a simulation envelope (object of
class `"envelope"`

) produced by any of the methods for
`envelope`

. Additionally, `Y`

must contain either

the simulated point patterns that were used to create the original envelope (so

`Y`

should have been created by calling`envelope`

with`savepatterns=TRUE`

);the summary functions of the simulated point patterns that were used to create the original envelope (so

`Y`

should have been created by calling`envelope`

with`savefuns=TRUE`

).

If the argument `fun`

is given, it should be a summary function
that can be applied to the simulated point patterns that were
used to create `Y`

. The envelope of
the summary function `fun`

for these point patterns
will be computed using the parameters specified in `…`

.

If `fun`

is not given, then:

If

`Y`

contains the summary functions that were used to compute the original envelope, then the new envelope will be computed from these original summary functions.Otherwise, if

`Y`

contains the simulated point patterns. then the \(K\) function`Kest`

will be applied to each of these simulated point patterns, and the new envelope will be based on the \(K\) functions.

The new envelope
will be computed using the parameters specified in `…`

.

See `envelope`

for a full list of envelope parameters.
Frequently-used parameters include `nrank`

and `nsim`

(to change the
number of simulations used and the significance level of the
envelope), `global`

(to change from pointwise to global
envelopes) and `VARIANCE`

(to compute the envelopes from the sample
moments instead of the ranks).

##### Value

An envelope (object of class `"envelope"`

.

##### See Also

##### Examples

```
# NOT RUN {
E <- envelope(cells, Kest, nsim=19, savefuns=TRUE, savepatterns=TRUE)
E2 <- envelope(E, nrank=2)
Eg <- envelope(E, global=TRUE)
EG <- envelope(E, Gest)
EL <- envelope(E, transform=expression(sqrt(./pi)))
# }
```

*Documentation reproduced from package spatstat, version 1.49-0, License: GPL (>= 2)*