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This is a small program-synthesis / learned-proposal experiment. The mutation,
selection, and evidence-acceptance algorithm is fixed. It is not unrestricted
recursive self-improvement. All operator-order predictions are local bracket
approximations; actual program losses determine selection.
"""
from __future__ import annotations
import argparse
import csv
import json
import time
from dataclasses import dataclass, asdict
from pathlib import Path
import numpy as np
@dataclass(frozen=True)
class Config:
dimension: int = 24
primitives: int = 12
underlying_fields: int = 4
responses: int = 2
train_states: int = 4
test_states: int = 24
generations: int = 5
candidate_budget: int = 12
seeds: int = 8
step_size: float = 0.15
elite_count: int = 3
seed_offset: int = 202611080
class Task:
def __init__(self, seed, cfg):
self.cfg = cfg
rng = np.random.default_rng(cfg.seed_offset + 10000 * seed)
d, m = cfg.dimension, cfg.primitives
rot, _ = np.linalg.qr(rng.normal(size=(d, d)))
eig = np.geomspace(0.04, 1., d)
self.H = (rot * eig) @ rot.T
basis = [np.eye(d)]
for _ in range(cfg.underlying_fields - 1):
o, _ = np.linalg.qr(rng.normal(size=(d, d)))
p = (o * rng.uniform(.2, 2., d)) @ o.T
p /= np.linalg.norm(p, 2)
basis.append(p)
mixing = np.vstack((np.eye(cfg.underlying_fields),
rng.dirichlet(np.ones(cfg.underlying_fields), size=m-cfg.underlying_fields)))
preconditioners = np.einsum('ib,bjk->ijk', mixing, np.asarray(basis))
self.maps = np.asarray([-p @ self.H for p in preconditioners])
self.c = rng.normal(size=d); self.c /= np.linalg.norm(self.c)
self.train = rng.normal(size=(cfg.train_states,d))
self.train /= np.linalg.norm(self.train,axis=1)[:,None]
test_rng = np.random.default_rng(cfg.seed_offset + 10000 * seed + 2222)
self.test = test_rng.normal(size=(cfg.test_states,d))
self.test /= np.linalg.norm(self.test,axis=1)[:,None]
def loss(self,x):
return float(.5*x @ self.H @ x)
def response(self,x):
return np.array([self.loss(x),self.c @ x])
def anchor(self,x):
g = self.H @ x
dh = np.vstack((g,self.c))
u = np.einsum('ijk,k->ji',self.maps,x)
v = np.einsum('ijk,j->ki',self.maps,g)
c = u.T @ v-v.T @ u
k = dh @ u
t = np.block([[c,k.T],[-k,np.zeros((len(k),len(k)))]])
left,s,_ = np.linalg.svd(t)
rank = int(np.count_nonzero(s>1e-10*max(s[0],1.)))
a = left[:,:rank].T
omega = a @ t @ a.T
q = k[0]
ell = np.r_[q,np.zeros(len(k))] @ a.T
return {'x':x,'g':g,'dh':dh,'h':self.response(x),'u':u,'c':c,
'k':k,'q':q,'t':t,'a':a,'omega':omega,'ell':ell,
'gate':a[:,self.cfg.primitives:],'rank':rank}
class Grammar:
def __init__(self,task):
self.task = task
self.m = task.cfg.primitives
self.nodes = [{'base':i,'depth':0} for i in range(self.m)]
def coefficients(self,index,h,cache=None):
if cache is None: cache={}
if index in cache: return cache[index]
node=self.nodes[index]
if 'base' in node:
b=np.eye(self.m)[node['base']]
db=np.zeros((self.m,len(h)))
else:
params=node['params']; beta=params[:,0]+params[:,1:] @ h
b=np.zeros(self.m);db=np.zeros((self.m,len(h)))
for j,parent in enumerate(node['parents']):
bp,dp=self.coefficients(parent,h,cache)
b+=beta[j]*bp
db+=beta[j]*dp+np.outer(bp,params[j,1:])
cache[index]=(b,db)
return b,db
def signature(self,index,anchor,cache=None):
if cache is None:cache={}
if index in cache:return cache[index]
node=self.nodes[index]
if 'base' in node:
e=anchor['a'][:,node['base']].copy()
else:
params=node['params'];beta=params[:,0]+params[:,1:] @ anchor['h']
e=np.zeros(anchor['rank'])
for j,parent in enumerate(node['parents']):
ep=self.signature(parent,anchor,cache)
e+=beta[j]*ep+(anchor['ell'] @ ep)*(anchor['gate'] @ params[j,1:])
cache[index]=e
return e
def add(self,parents,params,normalization_anchor):
index=len(self.nodes)
node={'parents':tuple(int(p) for p in parents),'params':params.copy(),
'depth':1+max(self.nodes[int(p)]['depth'] for p in parents)}
self.nodes.append(node)
b,_=self.coefficients(index,normalization_anchor['h'])
norm=np.linalg.norm(normalization_anchor['u'] @ b)
target=np.linalg.norm(normalization_anchor['g'])
scale=float(np.clip(target/max(norm,1e-14),.2,5.))
# This frozen scalar is part of the synthesized program, not a
# differentiable state-dependent normalization.
node['params']*=scale
return index
def field(self,index,x):
h=self.task.response(x)
b,_=self.coefficients(index,h)
u=np.einsum('ijk,k->ji',self.task.maps,x)
return u @ b
def full_jet(self,index,anchor,cache=None):
b,db=self.coefficients(index,anchor['h'],cache)
value=anchor['u'] @ b
jac=np.einsum('i,ijk->jk',b,self.task.maps)+anchor['u'] @ db @ anchor['dh']
return value,jac
def score(self,left,right,anchor,mode):
if mode=='minimal':
cache={}
e=self.signature(left,anchor,cache);f=self.signature(right,anchor,cache)
return float(e @ anchor['omega'] @ f)
cache={}
b,db=self.coefficients(left,anchor['h'],cache)
c,dc=self.coefficients(right,anchor['h'],cache)
if mode=='gate_blind':return float(b @ anchor['c'] @ c)
if mode=='first_jet':
z=np.r_[b,db.T @ anchor['q']]
w=np.r_[c,dc.T @ anchor['q']]
return float(z @ anchor['t'] @ w)
if mode=='full_jacobian':
y,dy=self.full_jet(left,anchor,cache)
z,dz=self.full_jet(right,anchor,cache)
return float(anchor['g'] @ (dz @ y-dy @ z))
raise ValueError(mode)
def execute(self,left,right,x,eta):
y=x+eta*self.field(left,x)
z=y+eta*self.field(right,y)
return self.task.loss(z)/max(self.task.loss(x),1e-30)
def evaluate_program(grammar,pair,states,anchors,mode,cfg,rng=None,both=False):
outcomes=[];order_accuracy=[];scoring_errors=[];full_errors=[]
choices=[]
left,right=pair
for x,anchor in zip(states,anchors):
if both:
ab=grammar.execute(left,right,x,cfg.step_size)
ba=grammar.execute(right,left,x,cfg.step_size)
reverse=ba<ab
value=min(ab,ba)
else:
if mode=='random_order':reverse=bool(rng.integers(0,2))
else:reverse=grammar.score(left,right,anchor,mode)>0
i,j=(right,left) if reverse else (left,right)
value=grammar.execute(i,j,x,cfg.step_size)
outcomes.append(value);choices.append(int(reverse))
return float(np.mean(outcomes)),choices
def one_run(seed,method,cfg):
task=Task(seed,cfg);grammar=Grammar(task)
train_anchors=[task.anchor(x) for x in task.train]
test_anchors=[task.anchor(x) for x in task.test]
rng=np.random.default_rng(cfg.seed_offset+10000*seed+3333)
mean=np.zeros((2,2,cfg.responses+1));mean[:,:,0]=.5
std=np.ones_like(mean);std[:,:,0]=.25
pool=list(range(cfg.primitives))
records=[];diagnostics=[];best=None;best_train=float('inf')
training_program_executions=0
prediction_anchors=0
start=time.perf_counter()
mode={'corrected':'minimal','generic_first_jet':'first_jet','full_jacobian':'full_jacobian',
'gate_blind':'gate_blind','random_order':'random_order',
'no_feedback':'minimal','direct_tournament':'minimal'}[method]
def held_out(pair):
# Evaluation never changes the trained program or proposal state.
# Tournament evaluates both orders; its additional test executions
# are recorded, not hidden as a free local ordering oracle.
local_rng=np.random.default_rng(cfg.seed_offset+seed+90000)
return evaluate_program(grammar,pair,task.test,test_anchors,mode,cfg,local_rng,
both=method=='direct_tournament')[0]
for generation in range(cfg.generations):
number=cfg.candidate_budget//2 if method=='direct_tournament' else cfg.candidate_budget
candidates=[]
for _ in range(number):
params=rng.normal(mean,std)
pair=[]
for side in range(2):
parents=[]
for _ in range(2):
options=list(range(cfg.primitives)) if rng.random()<.2 else pool
parents.append(int(rng.choice(options)))
pair.append(grammar.add(parents,params[side],train_anchors[0]))
loss,choices=evaluate_program(grammar,pair,task.train,train_anchors,mode,cfg,rng,
both=method=='direct_tournament')
training_program_executions+=cfg.train_states*(2 if method=='direct_tournament' else 1)
prediction_anchors+=cfg.train_states if method not in ('random_order','direct_tournament') else 0
candidates.append((loss,tuple(pair),params.copy(),choices))
if loss<best_train:
best_train=loss;best=tuple(pair)
candidates.sort(key=lambda x:x[0])
if method=='no_feedback':
chosen=rng.choice(len(candidates),size=min(cfg.elite_count,len(candidates)),replace=False)
elite=[candidates[i] for i in chosen]
else:
elite=candidates[:cfg.elite_count]
elite_params=np.asarray([x[2] for x in elite])
mean=.65*mean+.35*elite_params.mean(axis=0)
std=np.clip(.8*std+.2*elite_params.std(axis=0),.12,1.2)
pool=[index for c in elite for index in c[1]]
test_loss=held_out(best)
records.append({'seed':seed,'method':method,'generation':generation+1,
'training_program_executions':training_program_executions,
'train_best_loss_ratio':best_train,'heldout_loss_ratio':test_loss,
'mean_proposed_training_loss_ratio':float(np.mean([c[0] for c in candidates])),
'proposal_mean_change_norm':float(np.linalg.norm(mean-np.tile([.5,0,0],(2,2,1)))),
'proposal_std_mean':float(np.mean(std)),
'best_program_depth':max(grammar.nodes[i]['depth'] for i in best),
'nodes_generated':len(grammar.nodes)-cfg.primitives,
'minimal_signature_rank_min':min(a['rank'] for a in train_anchors),
'minimal_signature_rank_max':max(a['rank'] for a in train_anchors),
'test_program_executions':cfg.test_states*(2 if method=='direct_tournament' else 1)})
# Independent diagnostic probes are never exposed to the proposer.
# Their cost is evaluation overhead, excluded equally for all runs.
if method=='corrected':
for _,pair,_,_ in candidates:
for x,anchor in zip(task.test[:4],test_anchors[:4]):
exact=grammar.score(*pair,anchor,'full_jacobian')
compiled=grammar.score(*pair,anchor,'minimal')
firstjet=grammar.score(*pair,anchor,'first_jet')
blind=grammar.score(*pair,anchor,'gate_blind')
ab=grammar.execute(*pair,x,cfg.step_size)
ba=grammar.execute(pair[1],pair[0],x,cfg.step_size)
gap=ab-ba
valid=abs(gap)>1e-12
diagnostics.append({'seed':seed,'generation':generation+1,
'depth':max(grammar.nodes[i]['depth'] for i in pair),
'compiled_error':abs(compiled-exact),'first_jet_error':abs(firstjet-exact),
'blind_error':abs(blind-exact),'exact_bracket':exact,
'actual_loss_order_gap':gap,'non_tie':int(valid),
'compiled_correct_actual_order':int((compiled<=0)==(gap<=0)),
'blind_correct_actual_order':int((blind<=0)==(gap<=0))})
# All execute() calls evaluate both fields using the full primitive basis.
# A primitive Jacobian is a supplied matrix here, not a queried black box.
cost={'seed':seed,'method':method,'seconds_including_diagnostics':time.perf_counter()-start,
'training_program_executions':training_program_executions,
'training_primitive_field_evaluations':2*cfg.primitives*training_program_executions,
'prediction_score_count':prediction_anchors,
'base_jacobian_matrices_available':cfg.primitives,
'test_program_executions_all_checkpoints':sum(r['test_program_executions'] for r in records),
'note':'Program/primitive-value budgets match in training. Compiler arithmetic, supplied Jacobians, model operations, and diagnostic overhead are separately disclosed; no total-FLOP or wall-clock matching claim.'}
return records,diagnostics,cost
def write_csv(path,rows):
with path.open('w',newline='') as f:
writer=csv.DictWriter(f,fieldnames=list(rows[0]));writer.writeheader();writer.writerows(rows)
def main():
parser=argparse.ArgumentParser();parser.add_argument('--seeds',type=int,default=8)
parser.add_argument('--output',type=Path,default=Path(__file__).resolve().parents[1]/'results')
args=parser.parse_args();cfg=Config(seeds=args.seeds)
args.output.mkdir(exist_ok=True,parents=True)
methods=['corrected','generic_first_jet','full_jacobian','gate_blind','random_order','no_feedback','direct_tournament']
rows=[];diags=[];costs=[]
for seed in range(cfg.seeds):
for method in methods:
r,d,c=one_run(seed,method,cfg);rows+=r;diags+=d;costs.append(c)
summary=[]
for method in methods:
for generation in range(1,cfg.generations+1):
part=[r for r in rows if r['method']==method and r['generation']==generation]
x=np.asarray([r['heldout_loss_ratio'] for r in part])
summary.append({'method':method,'generation':generation,'mean_heldout_loss_ratio':float(x.mean()),
'std_heldout_loss_ratio':float(x.std(ddof=1)) if len(x)>1 else 0.,
'median_heldout_loss_ratio':float(np.median(x)),
'mean_train_best_loss_ratio':float(np.mean([r['train_best_loss_ratio'] for r in part])),
'mean_proposed_training_loss_ratio':float(np.mean([r['mean_proposed_training_loss_ratio'] for r in part])),
'mean_best_program_depth':float(np.mean([r['best_program_depth'] for r in part]))})
eq_errors={}
for other in ['generic_first_jet','full_jacobian']:
dif=[]
for seed in range(cfg.seeds):
for gen in range(1,cfg.generations+1):
a=next(r for r in rows if r['seed']==seed and r['method']=='corrected' and r['generation']==gen)
b=next(r for r in rows if r['seed']==seed and r['method']==other and r['generation']==gen)
dif.append(abs(a['heldout_loss_ratio']-b['heldout_loss_ratio']))
eq_errors[other]=max(dif)
nontie=[d for d in diags if d['non_tie']]
diagnostic_summary={'number_of_probes':len(diags),
'max_compiler_bracket_absolute_error':max(d['compiled_error'] for d in diags),
'max_firstjet_bracket_absolute_error':max(d['first_jet_error'] for d in diags),
'max_gateblind_bracket_absolute_error':max(d['blind_error'] for d in diags),
'mean_gateblind_bracket_absolute_error':float(np.mean([d['blind_error'] for d in diags])),
'compiled_actual_order_accuracy':float(np.mean([d['compiled_correct_actual_order'] for d in nontie])),
'gateblind_actual_order_accuracy':float(np.mean([d['blind_correct_actual_order'] for d in nontie])),
'non_tie_probes':len(nontie),'equivalent_compiler_search_trajectory_max_difference':eq_errors}
assert diagnostic_summary['max_compiler_bracket_absolute_error']<1e-9
assert max(eq_errors.values())<1e-10
out={'status':'Executed bounded optimizer-program evolution. The proposer learns parent choices and gate-parameter distributions from measured losses; mutation and selection algorithm remains fixed.',
'config':asdict(cfg),'methods':methods,'aggregate':summary,'diagnostics':diagnostic_summary,'costs':costs,
'scope':{'train':'four task starting states per independently generated quadratic system',
'heldout':'24 new initial states of the same quadratic system; never used for selection or distribution updates',
'not_tested':'new natural task families, LLMs, modification of the search algorithm itself, open-ended RSI',
'low_rank':'12 primitives are mixtures of four base linear fields, deliberately imposing a small response-relative form',
'ordering':'bracket predicts leading order only; selected programs are evaluated on the actual nonlinear gated fields',
'budget':'each method executes240 training two-step programs per seed; direct tournament uses half as many candidates and evaluates both orders',
'additional_costs':'All actual program executions charge24 primitive field evaluations. Jacobian matrices are supplied; compiler arithmetic and evolutionary updates are not FLOP-matched.',
'baseline':'Generic first-jet and full-Jacobian methods are mathematically equivalent and reproduce the same search. No superiority to them in discovery quality is asserted.',
'oracle':'The explicitly supplied quadratic Hessian admits a Newton step that solves the task. This study is not a state-of-the-art optimization performance claim.'}}
write_csv(args.output/'v2_pilot_program_search.csv',rows)
write_csv(args.output/'v2_pilot_bracket_diagnostics.csv',diags)
write_csv(args.output/'v2_pilot_program_costs.csv',costs)
(args.output/'v2_pilot_program_summary.json').write_text(json.dumps(out,indent=2)+'\n')
print(json.dumps({'final_results':[r for r in summary if r['generation']==cfg.generations],
'diagnostics':diagnostic_summary},indent=2))
if __name__=='__main__':main()
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