There's a more compelling illustration here: https://github.com/mdsumner/dputtruncat/blob/master/README.md
roms_names <- c("xi_rho", "eta_rho", "s_rho", "ocean_time", "s_w", "xi_u",
"eta_u", "xi_v", "eta_v", "tracer", "boundary", "xi_psi", "eta_psi")
axes_summary <- structure(c(1443L, 392L, 31L, 31L, 32L, 1442L, 392L, 1443L, 391L,
2L, 4L, 1442L, 391L), .Names = roms_names)
dput(axes_summary)