Critical density iteration

Input

iternuc N_ZAI ZAI₁ ZAI₂ ... ZAI_{N_ZAI} [ N_MAT MAT₁ MAT₂ ... MAX_{N_MAT} ]

`N_ZAI`	: number of different nuclides (ZAI) included in the iteration
`ZAI_i`	: the ZAI (e.g. 50100 for boron 10 ground state) of the nuclide to be included in the iteration
`N_MAT`	: number of different materials included in the iteration (optional parameter)
`MAT_i`	: the name of the material to be included in the iteration

Notes:

If a list of materials is not given, all materials that contain the included nuclides are included in the iteration.