find.marker: Find marker closest to a specified position
Description
Find the genetic marker closest to a specified position on a
chromosome.
Usage
find.marker(cross, chr, pos, index)
Arguments
cross
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.
index
A vector of numeric indices of the markers within
chromosomes.
Value
A vector of marker names (of the same length as the input pos),
corresponding to the markers nearest to the specified
chromosomes/positions (if pos is specified) or to the input
numeric indices (in index is specified).
Details
Provide one of pos or index.
If the input chr has length one, it is expanded to the same
length as the input pos or index.
If pos is specified and 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, positions specified by pos
are assumed to correspond to the female genetic map.