Opacity calculations for targets used in inertial confinement
fusion (ICF) needs sophisticated atomic physics models,
assuming a large number of configurations and transitions
to simulate the plasma. Depending on the degree of accuracy
for calculations of targets for ICF, some hydrodynamic-radiation
codes use multifrequency opacities or well mean opacities.In this work, using a sophisticated atomic physics code
for LTE opacity calculations, that provides well multifrequency
opacities or mean opacities, useful analytical opacity
formulas for several single elements used in ICF have been
generated, giving both Rosseland and Planck mean opacities
as a function of the plasma parameters.