# where.max

##### Find Location of Maximum in a Pixel Image

Finds the spatial location(s) where a given pixel image attains its maximum or minimum value.

##### Usage

```
where.max(x, first = TRUE)
where.min(x, first = TRUE)
```

##### Arguments

- x
A pixel image (object of class

`"im"`

).- first
Logical value. If

`TRUE`

(the default), then only one location will be returned. If`FALSE`

, then all locations where the maximum is achieved will be returned.

##### Details

This function finds the spatial location or locations where the
pixel image `x`

attains its maximum or minimum value.
The result is a point pattern giving the locations.

If `first=TRUE`

(the default), then only one location will
be returned, namely the location with the smallest \(y\) coordinate
value which attains the maximum or minimum.
This behaviour is analogous to the functions
`which.min`

and
`which.max`

.

If `first=FALSE`

, then the function returns
the locations of all pixels where the
maximum (or minimum) value is attained. This could be a large
number of points.

##### Value

A point pattern (object of class `"ppp"`

).

##### See Also

`Summary.im`

for computing the minimum and maximum
of pixel values;
`eval.im`

and `Math.im`

for mathematical
expressions involving images; `solutionset`

for finding
the set of pixels where a statement is true.

##### Examples

```
# NOT RUN {
D <- distmap(letterR, invert=TRUE)
plot(D)
plot(where.max(D), add=TRUE, pch=16, cols="green")
# }
```

*Documentation reproduced from package spatstat, version 1.55-1, License: GPL (>= 2)*