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spatstat.geom (version 3.3-2)

shift.im: Apply Vector Translation To Pixel Image

Description

Applies a vector shift to a pixel image

Usage

# S3 method for im
shift(X, vec=c(0,0), ..., origin=NULL)

Value

Another pixel image (of class "im") representing the result of applying the vector shift.

Arguments

X

Pixel image (object of class "im").

vec

Vector of length 2 representing a translation.

...

Ignored

origin

Location that will be shifted to the origin. Either a numeric vector of length 2 giving the location, or a point pattern containing only one point, or a list with two entries named x and y, or one of the character strings "centroid", "midpoint", "left", "right", "top", "bottom", "topleft", "bottomleft", "topright" or "bottomright" (partially matched).

Author

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

and Rolf Turner rolfturner@posteo.net

Details

The spatial location of each pixel in the image is translated by the vector vec. This is a method for the generic function shift.

If origin is given, the argument vec will be ignored; instead the shift will be performed so that the specified geometric location is shifted to the coordinate origin \((0,0)\). The argument origin should be either a numeric vector of length 2 giving the spatial coordinates of a location, or one of the character strings "centroid", "midpoint", "left", "right", "top", "bottom", "topleft", "bottomleft", "topright" or "bottomright" (partially matched). If origin="centroid" then the centroid of the window will be shifted to the origin. If origin="midpoint" then the centre of the bounding rectangle of the window will be shifted to the origin. If origin="bottomleft" then the bottom left corner of the bounding rectangle of the window will be shifted to the origin, and so on.

See Also

shift

Examples

Run this code
 # make up an image
 X <- setcov(unit.square())
 plot(X)

 Y <- shift(X, c(10,10))
 plot(Y)
 # no discernible difference except coordinates are different

 shift(X, origin="c")

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