s1215.py

from research import *
s=begin(1215,'Explain the exact cancellation in the Rounded head difference','Why do local rounding changes preserve the total430?',{},['C1214'])
rows=json.loads((ROOT/'model/whole_genealogy_rounded_changes.json').read_text())['rows'];eps=[x['rounded_dL']-x['exact_dL'] for x in rows];nz=[{'name':x['name'],'difference_error':e} for x,e in zip(rows,eps) if e]
a=artifact('model/whole_genealogy_rounded_head_cancellation.json',json.dumps({'located_difference_errors':nz,'sum_error':sum(eps),'exact_head':sum(x['exact_dL'] for x in rows),'rounded_head':sum(x['rounded_dL'] for x in rows),'interpretation':'The +4 Lamech change cancels two−2 early changes. A preserved total does not mean every row was preserved.'},indent=2)+'\n')
finish(s,{'cancellation':a,'located_errors':nz},'The Rounded Cumulative total remains430 because Lamech contributes+4 and Arphaxad/Shelah contribute−2 each. The cancellation explains the shared head while predicting an internal displacement field.','Reconstruct the internal rounding-displacement field rather than stop at its zero total.',{'cancels':sum(eps)==0,'heads430':sum(x['exact_dL'] for x in rows)==sum(x['rounded_dL'] for x in rows)==430})