File size: 6,048 Bytes
b887635
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
"""Shared data, configuration, and metric utilities."""

from __future__ import annotations

import json
import os
import random
from pathlib import Path
from typing import Any

import numpy as np
import torch
import yaml


REQUIRED_KEYS = ("init_value", "last_value", "sparse_mask")


def load_config(path: str | Path) -> dict[str, Any]:
    config_path = Path(path).resolve()
    with config_path.open("r", encoding="utf-8") as handle:
        config = yaml.safe_load(handle)
    if not isinstance(config, dict):
        raise ValueError(f"Config must be a mapping: {config_path}")
    return config


def atomic_write_json(path: str | Path, payload: object) -> None:
    destination = Path(path)
    destination.parent.mkdir(parents=True, exist_ok=True)
    temporary = destination.with_suffix(destination.suffix + ".tmp")
    temporary.write_text(json.dumps(payload, indent=2, ensure_ascii=False) + "\n", encoding="utf-8")
    os.replace(temporary, destination)


def seed_everything(seed: int) -> None:
    random.seed(seed)
    np.random.seed(seed % (2**32))
    torch.manual_seed(seed)
    if torch.cuda.is_available():
        torch.cuda.manual_seed_all(seed)


def load_split(
    data_root: str | Path,
    split: str,
    expected_count: int,
    expected_points: int = 4096,
) -> tuple[list[str], np.ndarray, np.ndarray, np.ndarray]:
    split_dir = Path(data_root) / split
    paths = sorted(split_dir.glob("*.npz"))
    if len(paths) != expected_count:
        raise ValueError(f"{split}: expected {expected_count} NPZ files, found {len(paths)}")
    names: list[str] = []
    inputs: list[np.ndarray] = []
    targets: list[np.ndarray] = []
    masks: list[np.ndarray] = []
    for path in paths:
        with np.load(path, allow_pickle=False) as sample:
            missing = [key for key in REQUIRED_KEYS if key not in sample.files]
            if missing:
                raise ValueError(f"{path}: missing arrays {missing}")
            values = [np.asarray(sample[key]) for key in REQUIRED_KEYS]
            for key, value in zip(REQUIRED_KEYS, values):
                if value.shape != (expected_points,) or value.dtype != np.float32:
                    raise ValueError(
                        f"{path}:{key} expected ({expected_points},) float32, got {value.shape} {value.dtype}"
                    )
                if not np.isfinite(value).all():
                    raise ValueError(f"{path}:{key} contains non-finite values")
            names.append(path.name)
            inputs.append(values[0])
            targets.append(values[1])
            masks.append(values[2])
    return names, np.stack(inputs), np.stack(targets), np.stack(masks)


def make_coordinate_features(grid_size: int, fourier_order: int) -> np.ndarray:
    axis = np.linspace(0.0, 1.0, grid_size, endpoint=True, dtype=np.float64)
    x_grid, y_grid = np.meshgrid(axis, axis, indexing="ij")
    raw = np.stack((x_grid.reshape(-1), y_grid.reshape(-1)), axis=1)
    feature_blocks = [raw]
    for frequency in range(1, fourier_order + 1):
        feature_blocks.append(np.sin(2.0 * np.pi * frequency * raw))
    for frequency in range(1, fourier_order + 1):
        feature_blocks.append(np.cos(2.0 * np.pi * frequency * raw))
    return np.concatenate(feature_blocks, axis=1).astype(np.float32)


def fit_target_transform(targets: np.ndarray) -> tuple[np.ndarray, float]:
    values = np.asarray(targets, dtype=np.float64)
    mean = values.mean(axis=0)
    centered = values - mean
    standard_deviation = float(centered.std(ddof=0))
    if not np.isfinite(standard_deviation) or standard_deviation <= 0:
        raise ValueError(f"Invalid target standard deviation: {standard_deviation}")
    return mean.astype(np.float32), standard_deviation


def balanced_train_queries(
    number_of_fields: int,
    points_per_field: int,
    total_queries: int,
    schedule_seed: int,
    zero_based_epoch: int,
) -> tuple[np.ndarray, np.ndarray]:
    base, remainder = divmod(total_queries, number_of_fields)
    if base + (1 if remainder else 0) > points_per_field:
        raise ValueError("balanced query request exceeds per-field points")
    rng = np.random.default_rng(schedule_seed + zero_based_epoch)
    field_order = rng.permutation(number_of_fields)
    counts = np.full(number_of_fields, base, dtype=np.int64)
    counts[field_order[:remainder]] += 1
    fields: list[np.ndarray] = []
    coordinates: list[np.ndarray] = []
    for field_index in range(number_of_fields):
        selected = np.sort(rng.choice(points_per_field, size=int(counts[field_index]), replace=False))
        fields.append(np.full(selected.size, field_index, dtype=np.int64))
        coordinates.append(selected.astype(np.int64, copy=False))
    field_indices = np.concatenate(fields)
    coordinate_indices = np.concatenate(coordinates)
    if field_indices.size != total_queries:
        raise RuntimeError("balanced sampler did not produce the requested query count")
    return field_indices, coordinate_indices


def fixed_tune_queries(
    number_of_fields: int,
    points_per_field: int,
    total_queries: int,
    seed: int = 0,
) -> tuple[np.ndarray, np.ndarray]:
    rng = np.random.default_rng(seed)
    global_indices = np.sort(
        rng.choice(number_of_fields * points_per_field, size=total_queries, replace=False)
    )
    return global_indices // points_per_field, global_indices % points_per_field


def relative_l2(target: np.ndarray, prediction: np.ndarray) -> float:
    target_values = np.asarray(target, dtype=np.float64).reshape(-1)
    prediction_values = np.asarray(prediction, dtype=np.float64).reshape(-1)
    return float(
        np.linalg.norm(target_values - prediction_values)
        / (np.linalg.norm(target_values) + 1.0e-12)
    )


def select_device(require_accelerator: bool) -> torch.device:
    if torch.cuda.is_available():
        return torch.device("cuda:0")
    if require_accelerator:
        raise RuntimeError("Formal training requires a visible DCU accelerator via torch.cuda")
    return torch.device("cpu")