countXO: Count number of obligate crossovers for each individual
Description
Count the number of obligate crossovers for each individual in a
cross, either by chromosome or overall.
Usage
countXO(cross, chr, bychr=FALSE)
Arguments
cross
An object of class cross. See
read.cross for details.
chr
Optional vector indicating the chromosomes to investigate.
This should be a vector of character strings referring to chromosomes
by name; numeric values are converted to strings. Refer to
chromosomes with a preceding - to have all chromosomes but
those considered. A logical (TRUE/FALSE) vector may also be used.
bychr
If TRUE, return counts for each individual chromosome; if
FALSE, return the overall number across the selected chromosomes.
Value
If bychr=TRUE, a matrix of counts is returned, with rows
corresponding to individuals and columns corresponding to
chromosomes.
If bychr=FALSE, a vector of counts (the total number of
crossovers across all selected chromosomes) is returned.
Details
For each individual we count the minimal number of crossovers that
explain the observed genotype data.