problem with calc_genoprob if no genetic map

[kbroman]

A problem reported on the R/qtl2 google group: if one doesn't have a genetic map and uses insert_pseudomarkers() to create one, for example using the physical map, then the output of calc_genoprob() ends up not having chromosome names, which leads to errors when trying to call calc_kinship().

Here's an example:

iron <- read_cross2(system.file("extdata", "iron.zip", package="qtl2"))            
gmap <- iron$gmap                                
iron$gmap <- NULL
pr <- calc_genoprob(iron, gmap)

names(pr)
# NULL

k <- calc_kinship(pr)
#  Error in probs[[1]] : subscript out of bounds

names(pr) <- names(gmap)
k <- calc_kinship(pr) # this now works