pub const NNLS_ITER_MAX: usize = 10;
iter_max of chi_sep_iLSQR_step3_func (not a parameter). The NNLS loop runs at most NNLS_ITER_MAX + 1 = 11 times: its counter starts at 1 and is tested with ≤ iter_max + 1.
iter_max
chi_sep_iLSQR_step3_func
NNLS_ITER_MAX + 1
≤ iter_max + 1