Fillig mass composition in COMPOUND card

Dear experts,

I had to prepare a fluka input using a python code which reads material data. For some materials, not all the atoms are present (for example, see f2 M2, f7, M7 entry in mat26 and mat27). My query is, is it right to keep f2 and M2 blank in the compound block? I mean there is no error while running, but I want to confirm if this is allowed or will this input skip any compound after the blank entry (i.e. f3 M3 and so on … ).

I tested by keeping the first entry f1, M1 blank and rest of them were filled, but then I got errors. So I am afraid that, although the input is running, it is not reading any compound entry after the blank entry.

I hope I have conveyed my query properly, otherwise please let me know.


Dear Riya,

Doing a quick check in FLAIR for one of the COMPOUND cards you have posted here, I see that the card is well read by FLUKA. Meaning that the empty slots you leave in these cards are taken as fx: 0.0 and Mx: 0.0. This also works leaving f1 and M1 as blank.

In order to confirm that FLUKA is reading properly the cards you are defining for the simulation, please search in the output file the card and you will get what is taken as input for the simulations.

As a note: active cards are preceded by “***** Next control card *****” in the output file.

Hope this helps you.

Kind regards,

Thank you @msabateg for the guidance.