mean.im
Maximum, Minimum, Mean, Median, Range or Sum of Pixel Values in an Image
Calculates the mean, median, range, sum, maximum or minimum of the pixel values in a pixel image.
Usage
"max"(x, ...) "min"(x, ...) "mean"(x, ...) "median"(x, ...) "range"(x, ...) "sum"(x, ...)
Arguments
 x
 A pixel image (object of class
"im"
).  ...
 Arguments passed to
mean.default
.
Details
These functions calculate the mean, median, range, sum, maximum
or minimum of the pixel values in the image
x
.
An object of class "im"
describes a pixel image. See im.object
)
for details of this class.
The function mean.im
is a method for the generic
function mean
for the class "im"
.
Similarly median.im
is a method for the generic
median
and range.im
is a method for range
.
If the image x
is logicalvalued, the mean value of x
is
the fraction of pixels that have the value TRUE
. The median is
not defined.
If the image x
is factorvalued, then the mean of x
is the mean of the integer codes of the pixel values. The median and range
are not defined.
Any arguments in ...
are passed to the default method,
for example mean.default
.
In particular, using the argument trim
will compute the
trimmed mean, as explained in the help for mean.default
.
Other information about an image can be obtained using
summary.im
or quantile.im
.
Value

A single number.
See Also
mean
,
median
,
range
,
sum
,
mean.default
,
median.default
,
range.default
,
quantile.im
,
anyNA.im
,
im.object
,
summary.im
.
Examples
X < as.im(function(x,y) {x^2}, unit.square())
mean(X)
median(X)
range(X)
mean(X, trim=0.05)