# with.hyperframe

##### Evaluate an Expression in Each Row of a Hyperframe

An expression, involving the names of columns in a hyperframe, is evaluated separately for each row of the hyperframe.

- Keywords
- manip, spatial, programming

##### Usage

```
## S3 method for class 'hyperframe':
with(data, expr, ...,
simplify = TRUE,
ee = NULL, enclos=NULL)
```

##### Arguments

- data
- A hyperframe (object of class
`"hyperframe"`

) containing data. - expr
- An Rlanguage expression to be evaluated.
- ...
- Ignored.
- simplify
- Logical. If
`TRUE`

, the return value will be simplified to a vector whenever possible. - ee
- Alternative form of
`expr`

, as an object of class`"expression"`

. - enclos
- An environment in which to search for objects that are
not found in the hyperframe. Defaults to
`parent.frame()`

.

##### Details

This function evaluates the expression `expr`

in each row
of the hyperframe `data`

. It is a method for the generic
function `with`

.
The argument `expr`

should be an Rlanguage expression
in which each variable name is either the name of a column in the
hyperframe `data`

, or the name of an object in the parent frame
(the environment in which `with`

was called.)
The argument `ee`

can be used as an alternative
to `expr`

and should be an expression object (of
class `"expression"`

).
For each row of `data`

, the expression will be evaluated
so that variables which are column names of `data`

are
interpreted as the entries for those columns in the current row.

For example, if a hyperframe `h`

has columns
called `A`

and `B`

, then `with(h, A != B)`

inspects
each row of `data`

in turn,
tests whether the entries in columns `A`

and `B`

are
equal, and returns the $n$ logical values.

##### Value

- Normally a list of length
$n$ (where $n$ is the number of rows) containing the results
of evaluating the expression for each row.
If
`simplify=TRUE`

and each result is a single atomic value, then the result is a vector or factor containing the same values.

##### See Also

##### Examples

```
# generate Poisson point patterns with intensities 10 to 100
H <- hyperframe(L=seq(10,100, by=10))
X <- with(H, rpoispp(L))
```

*Documentation reproduced from package spatstat, version 1.41-1, License: GPL (>= 2)*