# shift.ppp

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##### Apply Vector Translation To Point Pattern

Applies a vector shift to a point pattern.

Keywords
manip, spatial
##### Usage
# S3 method for ppp
shift(X, vec=c(0,0), …, origin=NULL)
##### Arguments
X

Point pattern (object of class "ppp").

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).

##### Details

The point pattern, and its window, are 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.

##### Value

Another point pattern (of class "ppp") representing the result of applying the vector shift.

shift, shift.owin, periodify, rotate, affine

• shift.ppp
##### Examples
# NOT RUN {
data(cells)
X <- shift(cells, c(2,3))

# }
# NOT RUN {
plot(X)
# no discernible difference except coordinates are different

# }
# NOT RUN {
plot(cells, pch=16)