This is the standard identity to derive nMx from nax and nqx.
lt_id_qa_m(nqx, nax, AgeInt)
numeric. Vector of age specific death probabilities.
numeric. Vector of average time spent in interval by those dying in interval.
integer. Vector of age class widths.
nMx vector of age specific death rates derived via identity.
Preston S, Heuveline P, Guillot M (2000). Demography: measuring and modeling population processes. Wiley-Blackwell.