These functions perform straightforward linear transformations on the generators of a zonotope, and the column vectors of a vector matroid
# S3 method for zonohedron
lintransform( x, W )
# S3 method for zonogon
lintransform( x, W )
# S3 method for matroid
lintransform( x, W )
If x
is a zonohedron (or zonogon),
lintransform(x)
returns the zonohedron (or zonogon)
whose generators are the generators of x
with the matrix
W
applied on the left side.
This function is optimized - it is not necessary
to transform the generators and start all over again.
If x
is a vector matroid, lintransform(x)
returns the matroid
whose generators are the generators of x
with the matrix
W
applied on the left side.
If x
is a matroid, but *not* a vector matroid,
it returns the original matroid and prints a warning message.
In case of error, e.g. invalid W
,
the function prints an error message and returns NULL
.
x
can be a vector matroid object, as returned from the constructor matroid()
that takes a matrix as input.
An invertible matrix that matches the rank of x
.
This invertibility is verified.
W
can also be a scalar; it is then replaced by that scalar
multiplied by the identity matrix of the appropriate rank.
Matroid - Wikipedia. https://en.wikipedia.org/w/index.php?title=Matroid&oldid=1086234057
rank()
,
matroid()