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Life table survivors from mortality rates: Deaths are recomputed from rates instead of survivor differences · case 04

d_x does not reconcile with l_x - l_{x+1}.

Member previewVariant 4 · 3 implementations · 12 checks per implementation

Case contract

Input q (per 100000, last must be 100000 else 'open table'; any outside [0,100000] -> 'invalid q') and radix (<=0 -> 'invalid radix'). l_0 = radix; l_{k+1} = l_k*(1-q_k) rounded half-up at every age; d_k = l_k - l_{k+1}. Return [l, d].

Why this case matters

Life-table arithmetic compounds across ages, so one misplaced index or assumption shifts every downstream value.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
half-death rounding tie	`[[9, 5, 0], [5, 5]]`	`[[9, 5, 0], [4, 5]]`	Failed

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