An object of class cross. See
read.cross for details.
chr
A vector of chromosome identifiers, or a single such.
pos
A vector of cM positions.
where
Indicates whether to look in the draws or
prob components of the input cross.
addchr
If TRUE, include something like "c5." at the
beginning of the names of non-pseudomarker locations, as in the output
of scanone; if FALSE, don't include this sort of string,
as in the genotype probabilities from calc.genoprob.
Value
A vector of pseudomarker names (of the same length as the input pos),
corresponding to the markers nearest to the specified chromosomes/positions.
Details
If the input chr has length one, it is expanded to the same
length as the input pos.
If multiple markers are exactly the same distance from the specified
position, one is chosen at random from among those with the most
genotype data.
For a cross with sex-specific maps, the input positions are assumed to
correspond to the female genetic map.