This function gives a set of numeric multipliers that can be used as a weight to calculate effective doses and irradiances. The BSWF is normalized at 300 nm.
numeric array of w.length (nm)
a numeric array of the same length as
w.length with values for
the BSWF normalized as in the original source. The returned values are
based on quantum effectiveness units.
In the original publication  describing the formulation, the long-end wavelength boundary is not specified, but 313.3 nm is usually used. The equation is coded here with the limit at 342 nm as at longer wavelengths the values increase with increasing wavelength. The effect on the RAF and doses of changing this boundary ican be substantial, and has been analysed by Micheletti et al. .
Caldwell, M. M. (1971) Solar UV irradiation and the growth and development of higher plants. In Giese, A. C. (Ed.) Photophysiology, Academic Press, 1971, 6, 131-177
 Micheletti, M. I. and R. D. Piacentini (2002) Irradiancia espetral solar UV-B y su relación con la efectividad de daño biológico a las plantas. ANALES AFA, 13, 242-248
 Micheletti, M. I.; Piacentini, R. D. & Madronich, S. (2003) Sensitivity of Biologically Active UV Radiation to Stratospheric Ozone Changes: Effects of Action Spectrum Shape and Wavelength Range Photochemistry and Photobiology, 78, 456-461