... The RCB carbon abundance remains an enigma ([ Asplund et al. ... The strength of a stellar absorption line represents the ratio of line opacity to continuous opacity in the atmosphere; both are related to the number density of the absorbing atoms and so provide the number ratio of line absorbers to continuum absorbers. ... Since the predominant continuum absorber in RCB atmospheres is neutral carbon, it has not yet proved possible to measure the carbon abundance from carbon absorption lines. ...

... 17.1 New features . ... Pure procedures . ... A function NULL to nullify a pointer . ... Complete version of END INTERFACE Pure functions are functions without side effects, and elemental functions are pure functions with only scalar arguments and with scalar result. ... Elemental functions are pure functions with only scalar dummy arguments (not pointers or procedures) and with scalar result (not pointer). That a function is elemental can be indicated with the new ELEMENTAL prefix. ...