Agent Conversation: google/gemini-3.1-pro-preview

Model: google/gemini-3.1-pro-preview
Total steps: 6
Messages: 29
UserStep 0

Task: optimization-evolution-strategy

Evolutionary Optimization Strategy Design

Research Question

Design a novel combination of selection, crossover, and mutation operators (and/or a novel evolutionary loop) for continuous black-box optimization that outperforms standard approaches across multiple benchmark functions.

Background

Evolutionary algorithms (EAs) are population-based metaheuristics for black-box optimization. The three core operators — selection, crossover, and mutation — together with the overall evolutionary loop design, determine an EA's performance. Standard approaches include:

  • Genetic Algorithms (GA): Tournament selection + Simulated Binary Crossover (SBX) + Polynomial Mutation
  • CMA-ES: Adapts the covariance matrix of a multivariate Gaussian to guide search
  • Differential Evolution (DE): Uses vector differences between population members for mutation

Each has strengths on different function landscapes (multimodal, ill-conditioned, high-dimensional), but no single strategy dominates all.

Task

Modify the editable section of custom_evolution.py (lines 87-225) to implement a novel or improved evolutionary strategy. You may modify:

  • custom_select(population, k, toolbox) — selection operator
  • custom_crossover(ind1, ind2) — crossover/recombination operator
  • custom_mutate(individual, lo, hi) — mutation operator
  • run_evolution(...) — the full evolutionary loop (you can restructure the algorithm entirely)

The DEAP library (deap.base, deap.creator, deap.tools) is available. You may also use numpy, scipy, math, and random.

Interface

  • Individuals: Lists of floats, each with a .fitness.values attribute (tuple of one float for minimization).
  • run_evolution must return (best_individual, fitness_history) where fitness_history is a list of best fitness per generation.
  • TRAIN_METRICS: Print TRAIN_METRICS gen=G best_fitness=F avg_fitness=A periodically (every 50 generations).
  • Respect the function signature and return types — the evaluation harness below the editable section is fixed.

Evaluation

Strategies are evaluated on 4 benchmarks (all minimization, lower is better):

BenchmarkFunctionDimensionsDomainGlobal Minimum
rastrigin-30dRastrigin30[-5.12, 5.12]0
rosenbrock-30dRosenbrock30[-5, 10]0
ackley-30dAckley30[-32.768, 32.768]0
rastrigin-100dRastrigin100[-5.12, 5.12]0

Metrics: best_fitness (final best value, lower is better) and convergence_gen (generation reaching near-final fitness).

Hints

  • Consider adaptive operator selection or parameter control (e.g., adapting crossover/mutation rates during evolution).
  • Hybrid approaches combining ideas from GA, DE, and ES can be effective.
  • Elitism (preserving the best individuals across generations) often helps.
  • For multimodal functions like R
AssistantStep 1edit
Tool Input
1{
2  "op": "replace",
3  "start_line": 88,
4  "end_line": 225,
5  "filename": "deap/custom_evolution.py",
6  "content": "def custom_select(population: list, k: int, toolbox=None) -> list:\n    \"\"\"Not used by the adaptive evolutionary loop directly.\"\"\"\n    return population[:k]\n\ndef custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:\n    \"\"\"Stubbed, crossover is handled dynamically within run_evolution.\"\"\"\n    return ind1, ind2\n\ndef custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:\n    \"\"\"Stubbed, mutation is handled dynamically within run_evolution.\"\"\"\n    return (individual,)\n\ndef run_evolution(\n    evaluate_func: Callable,\n    dim: int,\n    lo: float,\n    hi: float,\n    pop_size: int,\n    n_generations: int,\n    cx_prob: float,\n    mut_prob: float,\n    seed: int,\n) -> Tuple[list, list]:\n    \"\"\"Adaptive Eigen-Covariance Differential Evolution (AEC-DE).\n    \n    Combines Success-History Adaptive DE (L-SHADE) with adaptive operator selection\n    between standard binomial crossover and eigen-basis crossover. This creates a \n    scale-invariance and rotation-invariance strategy that learns the best operator\n    proportion during search. Also uses Opposition-based initialization.\n    \"\"\"\n    random.seed(seed)\n    np.random.seed(seed)\n\n    N_init = pop_size\n    N_min = 4\n    \n    # Opposition-Based Initialization\n    pop1 = np.random.uniform(lo, hi, (N_init, dim))\n    pop2 = lo + hi - pop1\n    \n    fit1 = np.array([evaluate_func(ind.tolist())[0] for ind in pop1])\n    fit2 = np.array([evaluate_func(ind.tolist())[0] for ind in pop2])\n    \n    pop_comb = np.vstack([pop1, pop2])\n    fit_comb = np.concatenate([fit1, fit2])\n    \n    best_idx = np.argsort(fit_comb)[:N_init]\n    pop = pop_comb[best_idx]\n    fitnesses = fit_comb[best_idx]\n    \n    # L-SHADE Memory\n    H = 6\n    M_CR = np.array([0.5] * H)\n    M_F = np.array([0.5] * H)\n    k_mem = 0\n    \n    archive = []\n    \n    P_eigen = 0.5  # Probability of using eigenvector-based crossover\n    fitness_history = []\n    \n    for gen in range(n_generations):\n        # Linear Population Size Reduction\n        N_current = int(round(N_init - (N_init - N_min) * (gen / n_generations)))\n        N_current = max(N_min, min(N_current, len(pop)))\n        \n        if N_current < len(pop):\n            sorted_idx = np.argsort(fitnesses)\n            pop = pop[sorted_idx[:N_current]]\n            fitnesses = fitnesses[sorted_idx[:N_current]]\n            \n        # Covariance Matrix & Eigenbasis\n        sorted_idx = np.argsort(fitnesses)\n        best_half_idx = sorted_idx[:max(3, N_current // 2)]\n        cov = np.cov(pop[best_half_idx].T)\n        cov += np.eye(dim) * 1e-8\n        eigenvalues, eigenvectors = np.linalg.eigh(cov)\n        B = eigenvectors\n        B_inv = B.T\n        \n        S_CR = []\n        S_F = []\n        delta_f = []\n        \n        delta_eigen = []\n        delta_standard = []\n        \n        new_pop = np.zeros_like(pop)\n        new_fitnesses = np.zeros(N_current)\n        \n        for i in range(N_current):\n            # Parameter Sampling\n            r_mem = random.randint(0, H - 1)\n            \n            # CR sampling\n            m_cr = M_CR[r_mem]\n            CR = np.random.normal(m_cr, 0.1)\n            CR = np.clip(CR, 0.0, 1.0)\n                \n            # F sampling\n            m_f = M_F[r_mem]\n            while True:\n                F = m_f + 0.1 * np.random.standard_cauchy()\n                if F > 0:\n                    break\n            F = min(F, 1.0)\n            \n            # current-to-pbest mutation\n            p_min = 2.0 / N_current\n            p = random.uniform(p_min, 0.2)\n            n_pbest = max(1, int(round(p * N_current)))\n            pbest_idx = sorted_idx[random.randint(0, n_pbest - 1)]\n            x_pbest = pop[pbest_idx]\n            \n            x_i = pop[i]\n            \n            candidates = list(range(N_current))\n            candidates.remove(i)\n            r1 = random.choice(candidates)\n            x_r1 = pop[r1]\n            \n            r2_candidates = list(range(N_current + len(archive)))\n            r2_candidates.remove(i)\n            if r1 in r2_candidates:\n                r2_candidates.remove(r1)\n                \n            if len(r2_candidates) > 0:\n                r2 = random.choice(r2_candidates)\n                if r2 < N_current:\n                    x_r2 = pop[r2]\n                else:\n                    x_r2 = archive[r2 - N_current]\n            else:\n                x_r2 = pop[random.choice(candidates)]\n                \n            v = x_i + F * (x_pbest - x_i) + F * (x_r1 - x_r2)\n            \n            # Adaptive Crossover\n            use_eigen = (random.random() < P_eigen)\n            \n            j_rand = random.randint(0, dim - 1)\n            mask = (np.random.rand(dim) < CR)\n            mask[j_rand] = True\n            \n            if use_eigen:\n                x_eig = B_inv @ x_i\n                v_eig = B_inv @ v\n                u_eig = np.where(mask, v_eig, x_eig)\n                u = B @ u_eig\n            else:\n                u = np.where(mask, v, x_i)\n                \n            # Bound Handling\n            out_of_bounds = (u < lo) | (u > hi)\n            if np.any(out_of_bounds):\n                u = np.where(u < lo, (x_i + lo) / 2.0, u)\n                u = np.where(u > hi, (x_i + hi) / 2.0, u)\n                \n            u_fit_val = evaluate_func(u.tolist())[0]\n            \n            if u_fit_val <= fitnesses[i]:\n                new_pop[i] = u\n                new_fitnesses[i] = u_fit_val\n                \n                if u_fit_val < fitnesses[i]:\n                    delta = fitnesses[i] - u_fit_val\n                    S_CR.append(CR)\n                    S_F.append(F)\n                    delta_f.append(delta)\n                    archive.append(x_i)\n                    \n                    if use_eigen:\n                        delta_eigen.append(delta)\n                    else:\n                        delta_standard.append(delta)\n            else:\n                new_pop[i] = x_i\n                new_fitnesses[i] = fitnesses[i]\n                \n        pop = new_pop\n        fitnesses = new_fitnesses\n        \n        # Update P_eigen\n        sum_eigen = sum(delta_eigen)\n        sum_standard = sum(delta_standard)\n        total_sum = sum_eigen + sum_standard\n        if total_sum > 0:\n            target_P_eigen = sum_eigen / total_sum\n            P_eigen = 0.9 * P_eigen + 0.1 * target_P_eigen\n            P_eigen = max(0.1, min(0.9, P_eigen))\n            \n        # Update archive size\n        if len(archive) > N_init:\n            archive = random.sample(archive, N_init)\n            \n        # Update M_CR, M_F memory\n        if len(S_F) > 0:\n            weights = np.array(delta_f) / (np.sum(delta_f) + 1e-10)\n            m_f_new = np.sum(weights * np.array(S_F)**2) / (np.sum(weights * np.array(S_F)) + 1e-10)\n            m_cr_new = np.sum(weights * np.array(S_CR))\n            \n            M_F[k_mem] = m_f_new\n            if m_cr_new > 0:\n                M_CR[k_mem] = m_cr_new\n                \n            k_mem = (k_mem + 1) % H\n            \n        best_fit = np.min(fitnesses)\n        fitness_history.append(best_fit)\n        \n        if (gen + 1) % 50 == 0 or gen == 0:\n            avg_fit = np.mean(fitnesses)\n            print(\n                f\"TRAIN_METRICS gen={gen+1} best_fitness={best_fit:.6e} \"\n                f\"avg_fitness={avg_fit:.6e} P_eigen={P_eigen:.3f}\",\n                flush=True,\n            )\n\n    # Return best individual\n    best_idx = np.argmin(fitnesses)\n    best_ind = creator.Individual(pop[best_idx].tolist())\n    best_ind.fitness.values = (fitnesses[best_idx],)\n    \n    return best_ind, fitness_history"
7}
Tool ResultStep 1
OK: Replaced lines 88..225 with 224 line(s) in deap/custom_evolution.py. Editable range: 87–311.

[Current file: deap/custom_evolution.py | editable: 87–311 | total: 389 lines]
    84| # EDITABLE SECTION — Design your evolutionary strategy below
    85| # (lines 87 to 225)
    86| # ================================================================
    87  
    88  def custom_select(population: list, k: int, toolbox=None) -> list:
    89      """Not used by the adaptive evolutionary loop directly."""
    90      return population[:k]
    91  
    92  def custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:
    93      """Stubbed, crossover is handled dynamically within run_evolution."""
    94      return ind1, ind2
    95  
    96  def custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:
    97      """Stubbed, mutation is handled dynamically within run_evolution."""
    98      return (individual,)
    99  
   100  def run_evolution(
   101      evaluate_func
AssistantStep 2test
Tool ResultStep 2
[Test #1] (2 tests remaining; call submit(n=1) to submit this result)


## Seed 42

### rastrigin-30d (scripts/rastrigin_30d.sh)
Training progress (rastrigin-30d):
TRAIN_METRICS gen=300 best_fitness=4.294725e+01 avg_fitness=6.083728e+01 P_eigen=0.100
TRAIN_METRICS gen=350 best_fitness=2.718301e+01 avg_fitness=4.481902e+01 P_eigen=0.100
TRAIN_METRICS gen=400 best_fitness=2.234556e+01 avg_fitness=3.194860e+01 P_eigen=0.100
TRAIN_METRICS gen=450 best_fitness=1.608998e+01 avg_fitness=2.159607e+01 P_eigen=0.100
TRAIN_METRICS gen=500 best_fitness=1.307924e+01 avg_fitness=1.379323e+01 P_eigen=0.100
best_fitness_rastrigin-30d: 1.307924e+01
convergence_gen_rastrigin-30d: 479

### rosenbrock-30d (scripts/rosenbrock_30d.sh)
Training progress (rosenbrock-30d):
TRAIN_METRICS gen=300 best_fitness=2.216148e+01 avg_fitness=2.220821e+01 P_eigen=0.885
TRAIN_METRICS gen=350 best_fitness=2.112032e+01 avg_fitness=2.120266e+01 P_eigen=0.897
TRAIN_METRICS gen=400 best_fitness=2.040464e+01 avg_fitness=2.04746
AssistantStep 3edit
Tool Input
1{
2  "op": "replace",
3  "start_line": 100,
4  "filename": "deap/custom_evolution.py",
5  "end_line": 311,
6  "content": "def run_evolution(\n    evaluate_func: Callable,\n    dim: int,\n    lo: float,\n    hi: float,\n    pop_size: int,\n    n_generations: int,\n    cx_prob: float,\n    mut_prob: float,\n    seed: int,\n) -> Tuple[list, list]:\n    from scipy.optimize import minimize\n    random.seed(seed)\n    np.random.seed(seed)\n    \n    N_init = pop_size\n    N_min = max(4, dim // 4)\n    \n    # OBL Initialization\n    pop1 = np.random.uniform(lo, hi, (N_init, dim))\n    pop2 = lo + hi - pop1\n    \n    fit1 = np.array([evaluate_func(ind.tolist())[0] for ind in pop1])\n    fit2 = np.array([evaluate_func(ind.tolist())[0] for ind in pop2])\n    \n    pop_comb = np.vstack([pop1, pop2])\n    fit_comb = np.concatenate([fit1, fit2])\n    \n    best_idx = np.argsort(fit_comb)[:N_init]\n    pop = pop_comb[best_idx]\n    fitnesses = fit_comb[best_idx]\n    \n    # SHADE memory\n    H = 6\n    M_CR = np.array([0.5] * H)\n    M_F = np.array([0.5] * H)\n    k_mem = 0\n    archive = []\n    \n    fitness_history = []\n    \n    # Adaptive Operator Selection Probabilities [Sep, Eigen, Std]\n    op_probs = [0.34, 0.33, 0.33]\n    \n    for gen in range(n_generations):\n        N_current = int(round(N_init - (N_init - N_min) * (gen / n_generations)))\n        N_current = max(N_min, min(N_current, len(pop)))\n        \n        if N_current < len(pop):\n            sorted_idx = np.argsort(fitnesses)\n            pop = pop[sorted_idx[:N_current]]\n            fitnesses = fitnesses[sorted_idx[:N_current]]\n            \n        if len(archive) > 0:\n            poly_pop = np.vstack((pop, np.array(archive)))\n        else:\n            poly_pop = pop\n            \n        if len(poly_pop) >= max(10, dim):\n            cov = np.cov(poly_pop.T) + np.eye(dim) * 1e-8\n            eigenvalues, eigenvectors = np.linalg.eigh(cov)\n            B = eigenvectors\n            B_inv = B.T\n            pop_cov_valid = True\n        else:\n            pop_cov_valid = False\n            \n        S_CR = []\n        S_F = []\n        delta_f = []\n        op_scores = [0.0, 0.0, 0.0]\n        \n        sorted_idx = np.argsort(fitnesses)\n        new_pop = np.zeros_like(pop)\n        new_fitnesses = np.zeros(N_current)\n        \n        for i in range(N_current):\n            r_mem = random.randint(0, H - 1)\n            CR_sampled = np.clip(np.random.normal(M_CR[r_mem], 0.1), 0.0, 1.0)\n            while True:\n                F_sampled = M_F[r_mem] + 0.1 * np.random.standard_cauchy()\n                if F_sampled > 0:\n                    break\n            F_sampled = min(F_sampled, 1.0)\n            \n            op = random.choices([0, 1, 2], weights=op_probs)[0]\n            \n            if op == 0:\n                CR = 0.05\n                F = F_sampled\n                use_eig = False\n            elif op == 1:\n                CR = CR_sampled\n                F = F_sampled\n                use_eig = pop_cov_valid\n            else:\n                CR = CR_sampled\n                F = F_sampled\n                use_eig = False\n                \n            p = random.uniform(2.0 / N_current, 0.2)\n            n_pbest = max(1, int(round(p * N_current)))\n            pbest_idx = sorted_idx[random.randint(0, n_pbest - 1)]\n            x_pbest = pop[pbest_idx]\n            \n            x_i = pop[i]\n            candidates = list(range(N_current))\n            candidates.remove(i)\n            r1 = random.choice(candidates)\n            x_r1 = pop[r1]\n            \n            r2_candidates = list(range(N_current + len(archive)))\n            r2_candidates.remove(i)\n            if r1 in r2_candidates:\n                r2_candidates.remove(r1)\n                \n            if len(r2_candidates) > 0:\n                r2 = random.choice(r2_candidates)\n                x_r2 = pop[r2] if r2 < N_current else archive[r2 - N_current]\n            else:\n                x_r2 = pop[random.choice(candidates)]\n                \n            v = x_i + F * (x_pbest - x_i) + F * (x_r1 - x_r2)\n            \n            j_rand = random.randint(0, dim - 1)\n            mask = (np.random.rand(dim) < CR)\n            mask[j_rand] = True\n            \n            if use_eig:\n                x_eig = B_inv @ x_i\n                v_eig = B_inv @ v\n                u_eig = np.where(mask, v_eig, x_eig)\n                u = B @ u_eig\n            else:\n                u = np.where(mask, v, x_i)\n                \n            out_of_bounds = (u < lo) | (u > hi)\n            if np.any(out_of_bounds):\n                u = np.where(u < lo, (x_i + lo) / 2.0, u)\n                u = np.where(u > hi, (x_i + hi) / 2.0, u)\n                \n            u_fit = evaluate_func(u.tolist())[0]\n            \n            if u_fit <= fitnesses[i]:\n                new_pop[i] = u\n                new_fitnesses[i] = u_fit\n                \n                if u_fit < fitnesses[i]:\n                    delta = fitnesses[i] - u_fit\n                    S_CR.append(CR)\n                    S_F.append(F)\n                    delta_f.append(delta)\n                    archive.append(x_i)\n                    op_scores[op] += delta\n            else:\n                new_pop[i] = x_i\n                new_fitnesses[i] = fitnesses[i]\n                \n        pop = new_pop\n        fitnesses = new_fitnesses\n        \n        # Memetic Local Search every 50 generations to supercharge accurate convergence\n        if (gen + 1) % 50 == 0 or gen == n_generations - 1:\n            curr_best_idx = np.argmin(fitnesses)\n            res = minimize(\n                lambda x: evaluate_func(x.tolist())[0],\n                pop[curr_best_idx],\n                bounds=[(lo, hi)] * dim,\n                method='L-BFGS-B',\n                options={'maxfun': 1000, 'ftol': 1e-9}\n            )\n            if res.fun < fitnesses[curr_best_idx]:\n                pop[curr_best_idx] = res.x\n                fitnesses[curr_best_idx] = res.fun\n                \n        total_score = sum(op_scores)\n        if total_score > 0:\n            target_probs = [s / total_score for s in op_scores]\n            op_probs = [0.8 * p + 0.2 * tp for p, tp in zip(op_probs, target_probs)]\n            op_probs = [max(0.1, p) for p in op_probs]\n            s_p = sum(op_probs)\n            op_probs = [p / s_p for p in op_probs]\n            \n        if len(archive) > N_init:\n            archive = random.sample(archive, N_init)\n            \n        if len(S_F) > 0:\n            weights = np.array(delta_f) / (np.sum(delta_f) + 1e-10)\n            M_F[k_mem] = np.sum(weights * np.array(S_F)**2) / (np.sum(weights * np.array(S_F)) + 1e-10)\n            M_CR[k_mem] = np.sum(weights * np.array(S_CR))\n            k_mem = (k_mem + 1) % H\n            \n        best_fit = np.min(fitnesses)\n        fitness_history.append(best_fit)\n        \n        if (gen + 1) % 50 == 0 or gen == 0:\n            avg_fit = np.mean(fitnesses)\n            print(f\"TRAIN_METRICS gen={gen+1} best_fitness={best_fit:.6e} avg_fitness={avg_fit:.6e}\", flush=True)\n            \n    best_idx = np.argmin(fitnesses)\n    toolbox = base.Toolbox()\n    toolbox.register(\"individual\", creator.Individual, pop[best_idx].tolist())\n    best_ind = toolbox.individual()\n    best_ind.fitness.values = (fitnesses[best_idx],)\n    \n    return best_ind, fitness_history"
7}
Tool ResultStep 3
OK: Replaced lines 100..311 with 206 line(s) in deap/custom_evolution.py. Editable range: 87–305.

[Current file: deap/custom_evolution.py | editable: 87–305 | total: 383 lines]
    84| # EDITABLE SECTION — Design your evolutionary strategy below
    85| # (lines 87 to 225)
    86| # ================================================================
    87  
    88  def custom_select(population: list, k: int, toolbox=None) -> list:
    89      """Not used by the adaptive evolutionary loop directly."""
    90      return population[:k]
    91  
    92  def custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:
    93      """Stubbed, crossover is handled dynamically within run_evolution."""
    94      return ind1, ind2
    95  
    96  def custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:
    97      """Stubbed, mutation is handled dynamically within run_evolution."""
    98      return (individual,)
    99  
   100  def run_evolution(
   101      evaluate_fun
AssistantStep 4test
Tool ResultStep 4
[Test #2] (1 test remaining; call submit(n=2) to submit this result)

### rastrigin-30d (scripts/rastrigin_30d.sh)
Training progress (rastrigin-30d):
TRAIN_METRICS gen=300 best_fitness=2.984875e+01 avg_fitness=6.040822e+01
TRAIN_METRICS gen=350 best_fitness=2.885379e+01 avg_fitness=4.612737e+01
TRAIN_METRICS gen=400 best_fitness=1.790926e+01 avg_fitness=3.567119e+01
TRAIN_METRICS gen=450 best_fitness=8.954632e+00 avg_fitness=2.465406e+01
TRAIN_METRICS gen=500 best_fitness=5.969754e+00 avg_fitness=1.358169e+01
best_fitness_rastrigin-30d: 5.969754e+00
convergence_gen_rastrigin-30d: 500

### rosenbrock-30d (scripts/rosenbrock_30d.sh)
Training progress (rosenbrock-30d):
TRAIN_METRICS gen=300 best_fitness=7.926182e+00 avg_fitness=1.547378e+01
TRAIN_METRICS gen=350 best_fitness=3.477899e+00 avg_fitness=1.133557e+01
TRAIN_METRICS gen=400 best_fitness=1.762897e-01 avg_fitness=7.499750e+00
TRAIN_METRICS gen=450 best_fitness=1.271064e-09 avg_fitness=3.902570e+00
TRAIN_METRICS gen=500 best_fitnes
AssistantStep 5edit
Tool Input
1{
2  "start_line": 205,
3  "content": "            cand_r1 = list(range(N_current))\n            cand_r1.remove(i)\n            r1 = random.choice(cand_r1)\n            x_r1 = pop[r1]\n            \n            cand_r2 = list(range(N_current + len(archive)))\n            cand_r2.remove(i)\n            if r1 in cand_r2:\n                cand_r2.remove(r1)\n                \n            if len(cand_r2) > 0:\n                r2 = random.choice(cand_r2)\n                x_r2 = pop[r2] if r2 < N_current else archive[r2 - N_current]\n            else:\n                x_r2 = pop[random.choice(cand_r1)]\n                r2 = 0 # fallback\n                \n            if op == 0:\n                CR = 0.0\n                F = F_sampled\n                use_eig = False\n                \n                cand_r3 = list(range(N_current))\n                cand_r3.remove(i)\n                if r1 in cand_r3: cand_r3.remove(r1)\n                if r2 < N_current and r2 in cand_r3: cand_r3.remove(r2)\n                \n                r3 = random.choice(cand_r3) if cand_r3 else random.choice(cand_r1)\n                x_r3 = pop[r3]\n                \n                v = x_r1 + F * (x_r2 - x_r3)\n            else:\n                if op == 1:\n                    CR = CR_sampled\n                    F = F_sampled\n                    use_eig = pop_cov_valid\n                else:\n                    CR = CR_sampled\n                    F = F_sampled\n                    use_eig = False\n                    \n                p = random.uniform(2.0 / N_current, 0.2)\n                n_pbest = max(1, int(round(p * N_current)))\n                pbest_idx = sorted_idx[random.randint(0, n_pbest - 1)]\n                x_pbest = pop[pbest_idx]\n                \n                v = x_i + F * (x_pbest - x_i) + F * (x_r1 - x_r2)\n                \n            j_rand = random.randint(0, dim - 1)\n            mask = (np.random.rand(dim) < CR)\n            mask[j_rand] = True\n            \n            if use_eig:",
4  "filename": "deap/custom_evolution.py",
5  "op": "replace",
6  "end_line": 228
7}
Tool ResultStep 5
OK: Replaced lines 205..228 with 53 line(s) in deap/custom_evolution.py. Editable range: 87–334.

[Current file: deap/custom_evolution.py | editable: 87–334 | total: 412 lines]
    84| # EDITABLE SECTION — Design your evolutionary strategy below
    85| # (lines 87 to 225)
    86| # ================================================================
    87  
    88  def custom_select(population: list, k: int, toolbox=None) -> list:
    89      """Not used by the adaptive evolutionary loop directly."""
    90      return population[:k]
    91  
    92  def custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:
    93      """Stubbed, crossover is handled dynamically within run_evolution."""
    94      return ind1, ind2
    95  
    96  def custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:
    97      """Stubbed, mutation is handled dynamically within run_evolution."""
    98      return (individual,)
    99  
   100  def run_evolution(
   101      evaluate_func
AssistantStep 6test
Tool ResultStep 6
[Test #3] (0 tests remaining)


## Seed 42

### rastrigin-30d (scripts/rastrigin_30d.sh)
=== RASTRIGIN (dim=30) ===
Bounds: [-5.12, 5.12], Pop: 200, Gens: 500
Traceback (most recent call last):
  File "/srv/home/bohanlyu/MLS-Bench/vendor/workspace/optimization-evolution-strategy/google_gemini-3.1-pro-preview_20260405_232405/deap/custom_evolution.py", line 412, in <module>
    main()
  File "/srv/home/bohanlyu/MLS-Bench/vendor/workspace/optimization-evolution-strategy/google_gemini-3.1-pro-preview_20260405_232405/deap/custom_evolution.py", line 384, in main
    best_ind, fitness_history = run_evolution(
                                ^^^^^^^^^^^^^^
  File "/srv/home/bohanlyu/MLS-Bench/vendor/workspace/optimization-evolution-strategy/google_gemini-3.1-pro-preview_20260405_232405/deap/custom_evolution.py", line 263, in run_evolution
    u = np.where(mask, v, x_i)
                          ^^^
NameError: name 'x_i' is not defined
ERROR conda.cli.main_run:execute(142): `conda run bash /srv
AssistantStep 1edit
Tool Input
1{
2  "op": "replace",
3  "filename": "deap/custom_evolution.py",
4  "content": "def custom_select(population: list, k: int, toolbox=None) -> list:\n    return population[:k]\n\ndef custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:\n    return ind1, ind2\n\ndef custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:\n    return (individual,)\n\ndef run_evolution(\n    evaluate_func: Callable,\n    dim: int,\n    lo: float,\n    hi: float,\n    pop_size: int,\n    n_generations: int,\n    cx_prob: float,\n    mut_prob: float,\n    seed: int,\n) -> Tuple[list, list]:\n    random.seed(seed)\n    np.random.seed(seed)\n\n    H = 6  # History size for adaptive DE\n    N_init = pop_size\n    N_min = max(4, dim)\n\n    # DEAP toolbox setup specifically for evaluation\n    toolbox = base.Toolbox()\n    toolbox.register(\"individual\", make_individual, toolbox, dim, lo, hi)\n    toolbox.register(\"population\", tools.initRepeat, list, toolbox.individual)\n    toolbox.register(\"evaluate\", evaluate_func)\n\n    # Initialize population randomly\n    pop = toolbox.population(n=N_init)\n    fitnesses = list(map(toolbox.evaluate, pop))\n    \n    pop_arr = np.array([list(ind) for ind in pop])\n    fits_arr = np.array([fit[0] for fit in fitnesses])\n\n    # Success History for F and CR\n    M_F = np.ones(H) * 0.5\n    M_CR = np.ones(H) * 0.5\n    k_hist = 0\n\n    archive = []\n    fitness_history = []\n\n    for gen in range(n_generations):\n        # Linear Population Size Reduction (LPSR)\n        ratio = gen / (n_generations - 1) if n_generations > 1 else 1.0\n        N_current = int(np.round(N_init - (N_init - N_min) * ratio))\n\n        # Trim population and archive\n        if len(pop_arr) > N_current:\n            sort_idx = np.argsort(fits_arr)\n            keep_idx = sort_idx[:N_current]\n            pop_arr = pop_arr[keep_idx]\n            fits_arr = fits_arr[keep_idx]\n\n        if len(archive) > N_current:\n            archive = random.sample(archive, N_current)\n\n        # Decide whether to use Eigen Crossover\n        compute_eigen = (gen > 10 and M_CR.mean() > 0.1)\n        p_eigen = 0.5  # Prob of choosing eigen vs standard binomial crossover\n        B = None\n        if compute_eigen:\n            sort_idx = np.argsort(fits_arr)\n            top_idx = sort_idx[:max(N_current // 2, dim + 1)]\n            top_pop = pop_arr[top_idx]\n            # Regularize covariance to prevent singularities\n            C = np.cov(top_pop, rowvar=False) + np.eye(dim) * 1e-8\n            try:\n                # Eigendecomposition\n                eigvals, eigvecs = np.linalg.eigh(C)\n                B = eigvecs\n            except np.linalg.LinAlgError:\n                compute_eigen = False\n\n        S_F, S_CR, delta_f = [], [], []\n        trials = np.zeros_like(pop_arr)\n        F_list, CR_list = [], []\n\n        r_idx = np.random.randint(0, H, size=N_current)\n        sort_idx = np.argsort(fits_arr)\n\n        for i in range(N_current):\n            # 1. Sample scaling factor F from Cauchy distribution\n            r = r_idx[i]\n            while True:\n                F_i = M_F[r] + 0.1 * np.random.standard_cauchy()\n                if F_i > 0:\n                    break\n            F_i = min(F_i, 1.0)\n\n            # 2. Sample crossover rate CR from Normal distribution\n            CR_i = np.clip(np.random.normal(M_CR[r], 0.1), 0.0, 1.0)\n\n            F_list.append(F_i)\n            CR_list.append(CR_i)\n\n            # 3. current-to-pbest/1 mutation strategy\n            p_i = random.uniform(2.0 / N_current, 0.2)\n            n_pbest = max(2, int(round(p_i * N_current)))\n            pbest = pop_arr[random.choice(sort_idx[:n_pbest])]\n\n            r1 = random.choice([x for x in range(N_current) if x != i])\n            avail_r2 = [x for x in range(N_current + len(archive)) if x != i and x != r1]\n            if not avail_r2: \n                avail_r2 = [r1]\n            r2_idx = random.choice(avail_r2)\n            \n            x_r2 = pop_arr[r2_idx] if r2_idx < N_current else archive[r2_idx - N_current]\n\n            mutant = pop_arr[i] + F_i * (pbest - pop_arr[i]) + F_i * (pop_arr[r1] - x_r2)\n\n            # 4. Crossover (Eigen or Standard Binomial)\n            if compute_eigen and random.random() < p_eigen:\n                x_prime = B.T @ pop_arr[i]\n                v_prime = B.T @ mutant\n                j_rand = random.randint(0, dim - 1)\n                mask = (np.random.rand(dim) < CR_i)\n                mask[j_rand] = True\n                u_prime = np.where(mask, v_prime, x_prime)\n                trial = B @ u_prime\n            else:\n                j_rand = random.randint(0, dim - 1)\n                mask = (np.random.rand(dim) < CR_i)\n                mask[j_rand] = True\n                trial = np.where(mask, mutant, pop_arr[i])\n\n            # 5. Boundary handling (midpoint bounce-back)\n            for j in range(dim):\n                if trial[j] < lo:\n                    trial[j] = (pop_arr[i][j] + lo) / 2.0\n                elif trial[j] > hi:\n                    trial[j] = (pop_arr[i][j] + hi) / 2.0\n            trials[i] = trial\n\n        # Batch evaluation\n        trial_fits = []\n        for i in range(N_current):\n            f = evaluate_func(trials[i].tolist())[0]\n            trial_fits.append(f)\n\n        # 6. Selection and Archive Update\n        for i in range(N_current):\n            if trial_fits[i] < fits_arr[i]:\n                S_F.append(F_list[i])\n                S_CR.append(CR_list[i])\n                delta_f.append(fits_arr[i] - trial_fits[i])\n                \n                archive.append(pop_arr[i].copy())\n                \n                pop_arr[i] = trials[i]\n                fits_arr[i] = trial_fits[i]\n            elif trial_fits[i] == fits_arr[i]:\n                pop_arr[i] = trials[i]\n\n        # 7. Adaptive parameters update\n        if S_F:\n            weights = np.array(delta_f)\n            w_sum = weights.sum()\n            weights = weights / w_sum if w_sum > 0 else np.ones(len(S_F)) / len(S_F)\n\n            M_F[k_hist] = np.sum(weights * np.array(S_F)**2) / (np.sum(weights * np.array(S_F)) + 1e-10)\n            M_CR[k_hist] = np.sum(weights * np.array(S_CR))\n            k_hist = (k_hist + 1) % H\n\n        # 8. Track best fitness\n        best_gen = np.min(fits_arr)\n        if gen == 0:\n            fitness_history.append(best_gen)\n        else:\n            fitness_history.append(min(best_gen, fitness_history[-1]))\n\n        if (gen + 1) % 50 == 0 or gen == 0:\n            avg_fit = np.mean(fits_arr)\n            print(\n                f\"TRAIN_METRICS gen={gen+1} best_fitness={fitness_history[-1]:.6e} avg_fitness={avg_fit:.6e}\",\n                flush=True\n            )\n\n    # Format the best individual for DEAP compatibility\n    best_idx = np.argmin(fits_arr)\n    best_ind = creator.Individual(pop_arr[best_idx].tolist())\n    best_ind.fitness.values = (fits_arr[best_idx],)\n\n    return best_ind, fitness_history",
5  "after_line": 1,
6  "start_line": 88,
7  "end_line": 225
8}
Tool ResultStep 1
OK: Replaced lines 88..225 with 190 line(s) in deap/custom_evolution.py. Editable range: 87–277.

[Current file: deap/custom_evolution.py | editable: 87–277 | total: 355 lines]
    84| # EDITABLE SECTION — Design your evolutionary strategy below
    85| # (lines 87 to 225)
    86| # ================================================================
    87  
    88  def custom_select(population: list, k: int, toolbox=None) -> list:
    89      return population[:k]
    90  
    91  def custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:
    92      return ind1, ind2
    93  
    94  def custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:
    95      return (individual,)
    96  
    97  def run_evolution(
    98      evaluate_func: Callable,
    99      dim: int,
   100      lo: float,
   101      hi: float,
   102      pop_size: int,
   103      n_generations: int,
   104      cx_prob: float,
   105      mut_prob: float,
   106      seed: int,
   107  ) -> Tu
AssistantStep 2test
Tool ResultStep 2
[Test #1] (2 tests remaining; call submit(n=1) to submit this result)

### rastrigin-30d (scripts/rastrigin_30d.sh)
Training progress (rastrigin-30d):
TRAIN_METRICS gen=300 best_fitness=3.977689e+01 avg_fitness=5.669058e+01
TRAIN_METRICS gen=350 best_fitness=3.103979e+01 avg_fitness=4.146701e+01
TRAIN_METRICS gen=400 best_fitness=1.904571e+01 avg_fitness=3.007221e+01
TRAIN_METRICS gen=450 best_fitness=1.578308e+01 avg_fitness=2.151213e+01
TRAIN_METRICS gen=500 best_fitness=1.102181e+01 avg_fitness=1.452042e+01
best_fitness_rastrigin-30d: 1.102181e+01
convergence_gen_rastrigin-30d: 498

### rosenbrock-30d (scripts/rosenbrock_30d.sh)
Training progress (rosenbrock-30d):
TRAIN_METRICS gen=300 best_fitness=2.104486e+01 avg_fitness=2.118451e+01
TRAIN_METRICS gen=350 best_fitness=1.940000e+01 avg_fitness=1.954140e+01
TRAIN_METRICS gen=400 best_fitness=1.782847e+01 avg_fitness=1.795073e+01
TRAIN_METRICS gen=450 best_fitness=1.663718e+01 avg_fitness=1.668233e+01
TRAIN_METRICS gen=500 best_fitne
AssistantStep 1edit
Tool Input
1{
2  "start_line": 87,
3  "content": "def custom_select(population: list, k: int, toolbox=None) -> list:\n    return population[:k]\n\ndef custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:\n    return ind1, ind2\n\ndef custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:\n    return (individual,)\n\ndef run_evolution(\n    evaluate_func: Callable,\n    dim: int,\n    lo: float,\n    hi: float,\n    pop_size: int,\n    n_generations: int,\n    cx_prob: float,\n    mut_prob: float,\n    seed: int,\n) -> Tuple[list, list]:\n    from deap import cma as deap_cma\n    \n    random.seed(seed)\n    np.random.seed(seed)\n    \n    lambda_cma = max(4, int(4 + 3 * math.log(dim)))\n    n_de = pop_size - lambda_cma\n    if n_de < 10:\n        n_de = pop_size // 2\n        lambda_cma = pop_size - n_de\n\n    centroid = [(lo + hi) / 2.0] * dim\n    sigma = (hi - lo) / 4.0\n    strategy = deap_cma.Strategy(centroid=centroid, sigma=sigma, lambda_=lambda_cma)\n    \n    P_DE = [creator.Individual([random.uniform(lo, hi) for _ in range(dim)]) for _ in range(n_de)]\n    for ind in P_DE:\n        ind.fitness.values = evaluate_func(ind)\n        \n    mu_CR = 0.5\n    mu_F = 0.5\n    c_adapt = 0.1\n    archive = []\n    \n    best_ever = None\n    best_ever_fit = float('inf')\n    fitness_history = []\n    \n    for gen in range(n_generations):\n        try:\n            cma_pop = strategy.generate(creator.Individual)\n        except Exception:\n            c_cen = best_ever[:] if best_ever else [(lo + hi) / 2.0] * dim\n            strategy = deap_cma.Strategy(centroid=c_cen, sigma=sigma/2.0, lambda_=lambda_cma)\n            cma_pop = strategy.generate(creator.Individual)\n            \n        de_trials = []\n        F_list, CR_list = [], []\n        \n        sorted_de = sorted(P_DE, key=lambda x: x.fitness.values[0])\n        n_pbest = max(1, int(0.05 * n_de))\n        best_pool = sorted_de[:n_pbest]\n        if best_ever is not None:\n            best_pool.insert(0, best_ever)\n            \n        for i in range(n_de):\n            CR_i = random.gauss(mu_CR, 0.1)\n            CR_i = max(0.0, min(1.0, CR_i))\n            \n            while True:\n                F_i = mu_F + 0.1 * np.random.standard_cauchy()\n                if F_i > 0:\n                    F_i = min(1.0, F_i)\n                    break\n                    \n            F_list.append(F_i)\n            CR_list.append(CR_i)\n            \n            pbest = random.choice(best_pool)\n            \n            r1 = random.randint(0, n_de - 1)\n            while r1 == i:\n                r1 = random.randint(0, n_de - 1)\n                \n            union_len = n_de + len(archive)\n            r2 = random.randint(0, union_len - 1)\n            retries = 0\n            while (r2 == i or r2 == r1) and retries < 10:\n                r2 = random.randint(0, union_len - 1)\n                retries += 1\n                \n            x_i = P_DE[i]\n            x_r1 = P_DE[r1]\n            x_r2 = P_DE[r2] if r2 < n_de else archive[r2 - n_de]\n            \n            trial = creator.Individual(x_i[:])\n            j_rand = random.randint(0, dim - 1)\n            for j in range(dim):\n                if random.random() < CR_i or j == j_rand:\n                    trial[j] = x_i[j] + F_i * (pbest[j] - x_i[j]) + F_i * (x_r1[j] - x_r2[j])\n                    \n            de_trials.append(trial)\n            \n        all_candidates = cma_pop + de_trials\n        for ind in all_candidates:\n            for j in range(dim):\n                ind[j] = max(lo, min(hi, ind[j]))\n                \n        fitnesses = list(map(evaluate_func, all_candidates))\n        for ind, fit in zip(all_candidates, fitnesses):\n            ind.fitness.values = fit\n            \n        gen_best = min(all_candidates, key=lambda x: x.fitness.values[0])\n        gen_best_fit = gen_best.fitness.values[0]\n        if gen_best_fit < best_ever_fit:\n            best_ever_fit = gen_best_fit\n            best_ever = creator.Individual(gen_best[:])\n            best_ever.fitness.values = gen_best.fitness.values\n            \n        fitness_history.append(best_ever_fit)\n        \n        try:\n            strategy.update(cma_pop)\n        except Exception:\n            c_cen = best_ever[:] if best_ever else [(lo + hi) / 2.0] * dim\n            strategy = deap_cma.Strategy(centroid=c_cen, sigma=sigma/2.0, lambda_=lambda_cma)\n            \n        S_F = []\n        S_CR = []\n        for i in range(n_de):\n            if de_trials[i].fitness.values[0] <= P_DE[i].fitness.values[0]:\n                if de_trials[i].fitness.values[0] < P_DE[i].fitness.values[0]:\n                    archive.append(creator.Individual(P_DE[i][:]))\n                    S_F.append(F_list[i])\n                    S_CR.append(CR_list[i])\n                P_DE[i] = de_trials[i]\n                \n        while len(archive) > n_de:\n            archive.pop(random.randint(0, len(archive) - 1))\n            \n        if S_F:\n            sum_f = sum(S_F)\n            if sum_f > 1e-6:\n                mu_F = (1 - c_adapt) * mu_F + c_adapt * (sum(f**2 for f in S_F) / sum_f)\n            mu_CR = (1 - c_adapt) * mu_CR + c_adapt * (sum(S_CR) / len(S_CR))\n            \n        if (gen + 1) % 50 == 0 or gen == 0:\n            avg_fit = sum(ind.fitness.values[0] for ind in P_DE) / len(P_DE)\n            print(f\"TRAIN_METRICS gen={gen+1} best_fitness={best_ever_fit:.6e} avg_fitness={avg_fit:.6e}\", flush=True)\n            \n    return best_ever, fitness_history",
4  "filename": "deap/custom_evolution.py",
5  "op": "replace",
6  "end_line": 225
7}
Tool ResultStep 1
OK: Replaced lines 87..225 with 151 line(s) in deap/custom_evolution.py. Editable range: 87–237.

[Current file: deap/custom_evolution.py | editable: 87–237 | total: 315 lines]
    84| # EDITABLE SECTION — Design your evolutionary strategy below
    85| # (lines 87 to 225)
    86| # ================================================================
    87  def custom_select(population: list, k: int, toolbox=None) -> list:
    88      return population[:k]
    89  
    90  def custom_crossover(ind1: list, ind2: list) -> Tuple[list, list]:
    91      return ind1, ind2
    92  
    93  def custom_mutate(individual: list, lo: float, hi: float) -> Tuple[list]:
    94      return (individual,)
    95  
    96  def run_evolution(
    97      evaluate_func: Callable,
    98      dim: int,
    99      lo: float,
   100      hi: float,
   101      pop_size: int,
   102      n_generations: int,
   103      cx_prob: float,
   104      mut_prob: float,
   105      seed: int,
   106  ) -> Tuple[list,
AssistantStep 2test