Shift starting points in a genetic map to a set of defined positions
Usage
shiftmap(object, offset=0)
Value
If the input is a map object, a map object is returned; if
the input is a cross object, a cross object is returned.
In either case, the positions of markers are shifted so that the
starting positions are as in offset.
Arguments
object
An object of class cross (see
read.cross for details) or map (see
sim.map for details).
offset
Defines the starting position
for each chromosome. This should be a
single value (to be used for all chromosomes) or a vector with length
equal to the number of chromosomes, defining individual starting
positions for each chromosome. For a sex-specific map (as in a 4-way
cross), we use the same offset for both the male and female maps.