# Mean and variance for multivariate truncated normal

Does anyone have a reference for mean and variance of a multivariate normal truncated along a single axis? I.e. $$\mathbb{E}[X | x_i > 0]$$ and $$Var[X | x_i > 0]$$, where $$X= [x_1,..,x_n] \sim \mathcal{N}(\mu, \Sigma)$$.

Check the R package tmvtnorm if you are interested in modeling. Link here.