How to calculate illuminance

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Hey radiance experts

I need to tun raytrace to calculate illuminance at each testpoint. I have all the files needed i.e. room.rad, light.rad and testpoints.txt file. But when I was trying to run rtrace to get calculated illuminance, then the output file is not generated as the way I want like I didn't get illuminance value at all the testpoints. I got the value at only few of the testpoints. Can someone explain me the reason or if there is any error in my rtrace command?

That's my sequence of command,

oconv room.rad light.rad > scene.octree

rtrace -I -oov -ab 2 -ad 1024 -ar 2048 -aa 0.05 scene.octree < testpoints.txt > result.txt

Thanks!