Applies any affine transformation of the plane (linear transformation plus vector shift) to a point pattern.

```
# S3 method for ppp
affine(X, mat=diag(c(1,1)), vec=c(0,0), …)
```

X

Point pattern (object of class `"ppp"`

).

mat

Matrix representing a linear transformation.

vec

Vector of length 2 representing a translation.

…

Arguments passed to `affine.owin`

affecting
the handling of the observation window, if it is a binary pixel
mask.

Another point pattern (of class `"ppp"`

) representing the
result of applying the affine transformation.

The point pattern, and its window, are subjected first to the
linear transformation represented by
`mat`

(multiplying on the left by `mat`

),
and are then translated by the vector `vec`

.

The argument `mat`

must be a nonsingular \(2 \times 2\)
matrix.

This is a method for the generic function `affine`

.

`affine`

,
`affine.owin`

,
`affine.psp`

,
`affine.im`

,
`flipxy`

,
`rotate`

,
`shift`

# NOT RUN { data(cells) # shear transformation X <- affine(cells, matrix(c(1,0,0.6,1),ncol=2)) if(interactive()) { plot(X) # rescale y coordinates by factor 1.3 plot(affine(cells, diag(c(1,1.3)))) } # }