Internal helper function for est_all_cond
est_cond(x, LD, YY, sigsnps, xtx = NULL)
data.table giving snp, beta and varbeta on remaining snps after conditioning
coloc dataset
named matrix of r
sum((Y-Ybar)^2)
names of snps to jointly condition on
optional, matrix X'X where X is the genotype matrix. If not available, will be estimated from LD, MAF, beta and sample size (the last three should be part of the coloc dataset)
Chris Wallace