Hi Minki!
I am sorry for my too late response to your kind comment. I read your script and it is so helpful. I am using Radiance to calculate ultraviolet intensity. So I don't need to convert radiance to illuminance, but need to revise the script for multiply points sampling.
Thank you as always.
The script can do that, you just need to remove the multiplication with Radiance's assumed luminous efficacy (179) and the color weighting (R*.265+G*.670+B*.065) in the last line. So let the script end as
(...)
total -if3 -m
And remove the backslash and the last line. I am assuming that you have set equal values in all channels (R=G=B in all source, material definitions).
Unfortunately, especially for small light sources of high intensity, you must set a rather high sampling density N not to miss out important sources. The script sends out rays to random directions, other then Radiance's integrated direct calculation which keeps a list of sources with known locations to check.
Cheers, Lars.