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Predicting the Strength of Composites

python main.py
python main.py mode=eval

下载预训练模型

| resnet18-v5-fold1 | resnet18-v5-fold2 | resnet18-v5-fold3 | resnet18-v5-fold4 | resnet18-v5-fold5 |

下载模型必要参数

| Saved_Output |

背景简介

材料的极限抗拉强度(UTS)是衡量复合材料抗拉伸破坏的核心指标,直接决定其应用安全性与可靠性。它是结构设计的关键依据,确保构件在拉伸载荷下不失效;也是材料选型的重要标准,匹配不同场景的强度需求,最终保障复合材料制品的性能上限。但由于复杂的形态-性能关系,预测其机械性能仍然较为困难,使用传统机器学习方法很难对其做出有效的预测。

针对材料科学领域中材料结构强度预测这一问题,通过X射线CT图像预测聚合物-陶瓷复合材料的极限抗拉强度(UTS)。相较于传统材料强度预测方法对于数据和模型的需求严苛,且需要耗费较长的时间成本,本项目通过深度学习技术,在小样本数据集的条件下,实现了较高精度的UTS值预测,提供了更快速且准确的工具。帮助研究人员快速了解材料的特性,并优化材料设计

本研究中使用卷积神经网络(CNN) 来分析冷烧结聚合物-陶瓷复合材料的 X 射线计算机断层扫描 (CT) 图像来应对这一问题。以形态特征作为输入的传统机器学习模型产生的准确性有限,而使用预训练的卷积神经网络,并使用集成学习进一步优化了模型。使用小型数据集来揭示复合材料中形态-结构-性能关系的替代机器学习方法,为衡量复合材料的性能提供了更精确且高效的解决方案。

目录结构

CNN_UTS/
├─ conf/
│    └─ resnet.yaml
├─ data_utils.py
├─ model_utils.py
├─ main.py
├─ requirements.txt
├─ readme.md
├─ resnet18-v5-finetune/
├─ outputs/
├─ Saved_Output/
└─ Dataset/
     ├─ Train_val/
     └─ Test/

2. 模型原理

本章节对基于卷积神经网络的材料拉伸强度预测模型的原理进行介绍。

该方法的主要思想是通过卷积神经网络建立材料微观结构图像与拉伸强度(UTS)之间的非线性映射关系。模型采用ResNet架构,能够有效提取图像中的深层特征信息。

本案例采用ResNet-18作为基础模型架构,主要包括以下几个部分:

  1. 输入层:接收 224×224×3 的RGB图像数据
  2. 卷积层:多个卷积块,包含残差连接
  3. 池化层:最大池化操作,降低特征图尺寸
  4. 全连接层:将特征映射到最终的预测值
  5. 输出层:输出预测的UTS值(MPa)

通过这种方式,我们可以自动学习材料微观结构图像中的关键特征,建立图像与性能之间的映射关系,实现准确的拉伸强度预测。

3. 模型实现

本章节我们讲解如何基于 PaddleScience 代码实现材料拉伸强度预测模型。本案例使用5折交叉验证进行模型训练和评估,并使用 PaddleScience 内置的各种功能模块。

3.1 数据格式说明

数据集下载链接:https://paddle-org.bj.bcebos.com/paddlescience/datasets/CNN_UTS/Dataset.zip

Image Name ...特征列... UTS (MPa) ...
IPP_10__40060.jpg ... 0.56 ...
... ... ... ...

本案例使用的数据集包含材料微观结构图像和对应的拉伸强度标签。数据集分为以下几个部分:

  1. 训练集:Dataset/Train_val/
  2. 测试集:Dataset/Test/

数据集结构如下:

  • 每个样本包含RGB图像和对应的UTS标签
  • 图像经过预处理,统一调整为224×224尺寸
  • 使用ImageNet预训练权重的标准化参数进行归一化

为了方便数据处理,我们使用了 make_dataset 函数来创建数据集:

examples/CNN_UTS/main.py
)
offline_transforms = paddle.vision.transforms.Compose(transforms=val_xform_list)

3.2 模型构建

本案例使用 PaddlePaddle 内置的 paddle.vision.models.resnet18 构建ResNet-18模型。模型的主要参数包括:

  1. 网络结构:ResNet-18 (2,2,2,2)
  2. 输入通道:3(RGB图像)
  3. 输出维度:1(UTS预测值)
  4. 预训练权重:ImageNet

模型定义代码如下:

examples/CNN_UTS/main.py
    shuffle=False,
    num_workers=0,
)
# define model

3.3 数据增强

为了提高模型的泛化能力,我们实现了多种数据增强策略:

  1. 随机水平翻转
  2. 随机垂直翻转
  3. 中心裁剪到224×224
  4. 标准化处理

数据增强配置如下:

examples/CNN_UTS/main.py
# create output directory
output_dir = cfg.output_dir
os.makedirs(output_dir, exist_ok=True)

# data augmentation config
transforms_list = [paddle.vision.transforms.CenterCrop(size=224)]
# Here you can add more augmentations based on cfg
transforms_list.append(paddle.vision.transforms.RandomHorizontalFlip(prob=0.5))
transforms_list.append(paddle.vision.transforms.RandomVerticalFlip(prob=0.5))
transforms_list.append(
    paddle.vision.transforms.Normalize(
        mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]
    )
)
online_transforms = paddle.vision.transforms.Compose(transforms=transforms_list)
val_xform_list = [paddle.vision.transforms.CenterCrop(size=224)]
val_xform_list.append(
    paddle.vision.transforms.Normalize(

3.4 训练策略

本案例采用5折交叉验证策略进行模型训练:

  1. 将训练数据分为5个fold
  2. 每个fold训练一个独立的模型
  3. 最终使用所有fold的预测结果进行集成

训练过程包括:

examples/CNN_UTS/main.py
test_loss_all_fold = []
min_epoch_all_fold = []
test_preds_history = []

for fold, (train_index, val_index) in enumerate(
    kf.split(train_val_dataset, uts_label, sample_id)
):
    print(f"\n===== Fold {fold+1}/{n_splits} started =====")
    print_gpu_memory()
    set_seed(cfg.seed)
    train_dataset = paddle.io.Subset(dataset=train_val_dataset, indices=train_index)
    val_dataset = paddle.io.Subset(dataset=train_val_dataset, indices=val_index)
    train_loader = paddle.io.DataLoader(
        dataset=train_dataset,

3.5 损失函数和优化器

使用均方误差损失函数进行回归任务:

examples/CNN_UTS/main.py
model = paddle.vision.models.resnet18(pretrained=True)

使用Adam优化器进行参数更新:

examples/CNN_UTS/main.py
# modify the last layer to adapt to the regression task
model.fc = paddle.nn.Linear(model.fc.weight.shape[0], 1)
model.to(device)

3.6 模型评估

评估过程包括:

  1. 计算MSE和R²指标
  2. 生成parity plot和violin plot
  3. 进行集成预测

评估器构建代码如下:

examples/CNN_UTS/main.py
avg_train_loss = (
    sum(batch_losses) / len(batch_losses) if batch_losses else 0
)
print(
    f"[Fold {fold+1}][Epoch {epoch+1}] Training set average Loss: {avg_train_loss:.6f}"
)
model.eval()
with paddle.no_grad():
    val_loss = 0
    k = 0
    preds_val = []
    true_labels_val = []
    for images, groups, labels in val_loader:
        try:
            images = offline_transforms(images)
            outputs = model(images)
            val_loss += criterion(outputs.squeeze(), labels).item() * len(
                images
            )
            k += len(images)
            preds_val.append(outputs.squeeze())
            true_labels_val.append(labels)
        except RuntimeError as e:
            if "out of memory" in str(e).lower():
                print(
                    "Validation stage GPU memory is insufficient, skipping current batch"
                )
                paddle.device.cuda.empty_cache()
                continue
            else:
                print(f"Error occurred during validation: {e}")
                continue
        except Exception as e:

4. 完整代码

examples/CNN_UTS/main.py
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import os

import hydra
import matplotlib.pyplot as plt
import numpy as np
import paddle
import tqdm
from data_utils import device2str
from data_utils import make_dataset
from model_utils import set_seed
from omegaconf import DictConfig
from sklearn.metrics import mean_squared_error
from sklearn.metrics import r2_score
from sklearn.model_selection import StratifiedGroupKFold


def print_gpu_memory():
    """print GPU memory usage"""
    if paddle.device.cuda.device_count() > 0:
        try:
            memory_allocated = paddle.device.cuda.memory_allocated() / 1024**3  # GB
            memory_reserved = paddle.device.cuda.memory_reserved() / 1024**3  # GB
            print(
                f"GPU memory usage: {memory_allocated:.2f}GB / {memory_reserved:.2f}GB"
            )
        except Exception:
            print("Unable to retrieve GPU memory information")


def train(cfg):
    # set random seed
    set_seed(cfg.seed)
    device = device2str(cfg.device)

    # check GPU availability
    if "gpu" in device:
        if not paddle.device.cuda.device_count():
            print(
                "Warning: Configured for GPU training but no GPU detected, using CPU instead"
            )
            device = "cpu"
        else:
            print(f"Using GPU device: {device}")
            # Set GPU device
            paddle.set_device(device)

    num_epochs = cfg.train.epochs
    n_splits = cfg.train.n_splits
    Batch_size = cfg.train.batch_size
    lr = cfg.train.lr
    N_skip = cfg.data.N

    # create output directory
    output_dir = cfg.output_dir
    os.makedirs(output_dir, exist_ok=True)

    # data augmentation config
    transforms_list = [paddle.vision.transforms.CenterCrop(size=224)]
    # Here you can add more augmentations based on cfg
    transforms_list.append(paddle.vision.transforms.RandomHorizontalFlip(prob=0.5))
    transforms_list.append(paddle.vision.transforms.RandomVerticalFlip(prob=0.5))
    transforms_list.append(
        paddle.vision.transforms.Normalize(
            mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]
        )
    )
    online_transforms = paddle.vision.transforms.Compose(transforms=transforms_list)
    val_xform_list = [paddle.vision.transforms.CenterCrop(size=224)]
    val_xform_list.append(
        paddle.vision.transforms.Normalize(
            mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]
        )
    )
    offline_transforms = paddle.vision.transforms.Compose(transforms=val_xform_list)

    # datasets
    train_val_dataset = make_dataset(cfg.data.train_path, N=N_skip, device=device)
    test_dataset = make_dataset(cfg.data.test_path, N=N_skip, device=device)

    kf = StratifiedGroupKFold(n_splits=n_splits)
    uts_label = [it[1][0] for it in train_val_dataset]
    sample_id = [it[1][1] for it in train_val_dataset]

    val_loss_all_fold = []
    test_loss_all_fold = []
    min_epoch_all_fold = []
    test_preds_history = []

    for fold, (train_index, val_index) in enumerate(
        kf.split(train_val_dataset, uts_label, sample_id)
    ):
        print(f"\n===== Fold {fold+1}/{n_splits} started =====")
        print_gpu_memory()
        set_seed(cfg.seed)
        train_dataset = paddle.io.Subset(dataset=train_val_dataset, indices=train_index)
        val_dataset = paddle.io.Subset(dataset=train_val_dataset, indices=val_index)
        train_loader = paddle.io.DataLoader(
            dataset=train_dataset,
            batch_size=Batch_size,
            shuffle=True,
            num_workers=0,
        )
        val_loader = paddle.io.DataLoader(
            dataset=val_dataset,
            batch_size=128,
            shuffle=False,
            num_workers=0,
        )
        test_loader = paddle.io.DataLoader(
            dataset=test_dataset,
            batch_size=128,
            shuffle=False,
            num_workers=0,
        )
        # define model
        model = paddle.vision.models.resnet18(pretrained=True)
        # modify the last layer to adapt to the regression task
        model.fc = paddle.nn.Linear(model.fc.weight.shape[0], 1)
        model.to(device)
        criterion = paddle.nn.MSELoss()
        optimizer = paddle.optimizer.Adam(
            parameters=model.parameters(), learning_rate=lr, weight_decay=0.0
        )
        val_loss_history = []
        test_loss_history = []
        test_preds_best = None
        pbar = tqdm.tqdm(range(num_epochs))
        for epoch in pbar:
            print(f"\n--- Fold {fold+1} Epoch {epoch+1}/{num_epochs} ---")
            model.train()
            set_seed(cfg.seed)
            batch_losses = []
            for i, (images, groups, labels) in enumerate(train_loader):
                try:
                    images = online_transforms(images)
                    outputs = model(images)
                    loss = criterion(outputs.squeeze(), labels)
                    optimizer.clear_gradients(set_to_zero=False)
                    loss.backward()
                    optimizer.step()
                    batch_losses.append(loss.item())
                    print(
                        f"[Fold {fold+1}][Epoch {epoch+1}][Batch {i+1}/{len(train_loader)}] Loss: {loss.item():.6f}"
                    )
                except RuntimeError as e:
                    if "out of memory" in str(e).lower():
                        print("GPU memory is insufficient, skipping current batch")
                        paddle.device.cuda.empty_cache()
                        continue
                    else:
                        print(f"Error occurred during training: {e}")
                        continue
                except Exception as e:
                    print(f"Error occurred during training: {e}")
                    continue
            avg_train_loss = (
                sum(batch_losses) / len(batch_losses) if batch_losses else 0
            )
            print(
                f"[Fold {fold+1}][Epoch {epoch+1}] Training set average Loss: {avg_train_loss:.6f}"
            )
            model.eval()
            with paddle.no_grad():
                val_loss = 0
                k = 0
                preds_val = []
                true_labels_val = []
                for images, groups, labels in val_loader:
                    try:
                        images = offline_transforms(images)
                        outputs = model(images)
                        val_loss += criterion(outputs.squeeze(), labels).item() * len(
                            images
                        )
                        k += len(images)
                        preds_val.append(outputs.squeeze())
                        true_labels_val.append(labels)
                    except RuntimeError as e:
                        if "out of memory" in str(e).lower():
                            print(
                                "Validation stage GPU memory is insufficient, skipping current batch"
                            )
                            paddle.device.cuda.empty_cache()
                            continue
                        else:
                            print(f"Error occurred during validation: {e}")
                            continue
                    except Exception as e:
                        print(f"Error occurred during validation: {e}")
                        continue
                val_loss /= k
                preds_val = paddle.concat(x=preds_val, axis=0).detach().cpu().numpy()
                true_labels_val = (
                    paddle.concat(x=true_labels_val, axis=0).detach().cpu().numpy()
                )
                print(
                    f"[Fold {fold+1}][Epoch {epoch+1}] Validation set Loss: {val_loss:.6f}"
                )
                test_loss = 0
                k = 0
                preds_test = []
                true_labels_test = []
                for images, groups, labels in test_loader:
                    try:
                        images = offline_transforms(images)
                        outputs = model(images)
                        test_loss += criterion(outputs.squeeze(), labels).item() * len(
                            images
                        )
                        k += len(images)
                        preds_test.append(outputs.squeeze())
                        true_labels_test.append(labels)
                    except RuntimeError as e:
                        if "out of memory" in str(e).lower():
                            print(
                                "Testing stage GPU memory is insufficient, skipping current batch"
                            )
                            paddle.device.cuda.empty_cache()
                            continue
                        else:
                            print(f"Error occurred during testing: {e}")
                            continue
                    except Exception as e:
                        print(f"Error occurred during testing: {e}")
                        continue
                test_loss /= k
                preds_test = paddle.concat(x=preds_test, axis=0).detach().cpu().numpy()
                true_labels_test = (
                    paddle.concat(x=true_labels_test, axis=0).detach().cpu().numpy()
                )
                print(
                    f"[Fold {fold+1}][Epoch {epoch+1}] Testing set Loss: {test_loss:.6f}"
                )
            val_loss_history.append(val_loss)
            test_loss_history.append(test_loss)
            if val_loss == np.min(val_loss_history):
                test_preds_best = preds_test.copy()
                paddle.save(
                    obj=model.state_dict(),
                    path=f"./resnet18-v5-finetune/resnet18-v5-fold{fold + 1}.pdparams",
                )
                print(
                    f"[Fold {fold+1}][Epoch {epoch+1}] Validation set Loss new low, model parameters saved!"
                )
            pbar.set_postfix_str(
                f"Train {avg_train_loss:.3e}, Val {val_loss:.3e}, Test {test_loss:.3e}"
            )
        min_epoch = np.argmin(val_loss_history)
        val_loss_all_fold.append(val_loss_history[min_epoch])
        min_epoch_all_fold.append(min_epoch + 1)
        test_loss_all_fold.append(test_loss_history[min_epoch])
        test_preds_history.append(test_preds_best)

        # Collect all predictions and labels for current fold
        print(f"Collecting predictions for Fold {fold+1}...")

        # predict on train, val, test sets
        model.eval()
        with paddle.no_grad():
            preds_train = []
            true_labels_train = []
            train_groups_fold = []
            train_samples_id = []

            for images, groups, labels in train_loader:
                try:
                    images = offline_transforms(images)
                    outputs = model(images)
                    preds_train.append(outputs.numpy())
                    true_labels_train.append(labels.numpy())
                    train_groups_fold.extend(groups[0].numpy())
                    train_samples_id.extend(groups[1].numpy())
                except Exception as e:
                    print(f"Error occurred during training set prediction: {e}")
                    continue

            # Validation set prediction
            preds_val = []
            true_labels_val = []
            val_groups_fold = []
            val_samples_id = []

            for images, groups, labels in val_loader:
                try:
                    images = offline_transforms(images)
                    outputs = model(images)
                    preds_val.append(outputs.numpy())
                    true_labels_val.append(labels.numpy())
                    val_groups_fold.extend(groups[0].numpy())
                    val_samples_id.extend(groups[1].numpy())
                except Exception as e:
                    print(f"Error occurred during validation set prediction: {e}")
                    continue

            # Test set prediction
            preds_test = []
            true_labels_test = []
            test_groups_fold = []
            test_samples_id = []

            for images, groups, labels in test_loader:
                try:
                    images = offline_transforms(images)
                    outputs = model(images)
                    preds_test.append(outputs.numpy())
                    true_labels_test.append(labels.numpy())
                    test_groups_fold.extend(groups[0].numpy())
                    test_samples_id.extend(groups[1].numpy())
                except Exception as e:
                    print(f"Error occurred during test set prediction: {e}")
                    continue

        # Flatten results
        preds_train = np.concatenate(preds_train)
        true_labels_train = np.concatenate(true_labels_train)
        preds_val = np.concatenate(preds_val)
        true_labels_val = np.concatenate(true_labels_val)
        preds_test = np.concatenate(preds_test)
        true_labels_test = np.concatenate(true_labels_test)

        # Get unique groups and sample IDs
        unique_val_groups = sorted(set(val_groups_fold))
        unique_sample_id = sorted(set(val_samples_id))

        # Save current fold's predictions and labels
        np.save(os.path.join(output_dir, f"preds_train_fold{fold+1}.npy"), preds_train)
        np.save(os.path.join(output_dir, f"preds_val_fold{fold+1}.npy"), preds_val)
        np.save(os.path.join(output_dir, f"preds_test_fold{fold+1}.npy"), preds_test)
        np.save(
            os.path.join(output_dir, f"true_labels_train_fold{fold+1}.npy"),
            true_labels_train,
        )
        np.save(
            os.path.join(output_dir, f"true_labels_val_fold{fold+1}.npy"),
            true_labels_val,
        )
        np.save(
            os.path.join(output_dir, f"true_labels_test_fold{fold+1}.npy"),
            true_labels_test,
        )

        # Save sample IDs
        np.save(
            os.path.join(output_dir, f"sample_ids_train_fold{fold+1}.npy"),
            train_samples_id,
        )
        np.save(
            os.path.join(output_dir, f"sample_ids_val_fold{fold+1}.npy"), val_samples_id
        )
        np.save(
            os.path.join(output_dir, f"sample_ids_test_fold{fold+1}.npy"),
            test_samples_id,
        )

        # Save unique groups and sample IDs
        np.save(
            os.path.join(output_dir, f"unique_val_groups_fold_{fold+1}.npy"),
            unique_val_groups,
        )
        np.save(
            os.path.join(output_dir, f"unique_sample_id_fold_{fold+1}.npy"),
            unique_sample_id,
        )

        print(f"Fold {fold+1} prediction results saved")
        print(
            f"===== Fold {fold+1} completed, Best validation Loss: {val_loss_all_fold[-1]:.6f}, Best epoch: {min_epoch+1} =====\n"
        )
    # Result statistics and output
    print(f"Validation for five folds: {val_loss_all_fold}")
    print(
        f"Lowest validation loss for each fold occurred at epochs: {min_epoch_all_fold}"
    )
    print(
        f"Mean validation loss: {np.mean(val_loss_all_fold):.4f} ± {np.std(val_loss_all_fold):.4f}"
    )
    print(
        f"Mean test loss: {np.mean(test_loss_all_fold):.4f} ± {np.std(test_loss_all_fold):.4f}"
    )

    # Ensemble prediction
    print("\nStarting ensemble prediction...")
    # Ensure test_preds_history is a numpy array
    test_preds_history = np.array(test_preds_history)
    print(f"Ensemble prediction shape: {test_preds_history.shape}")

    # Ensure correct data shape, remove extra dimensions
    if test_preds_history.ndim == 3 and test_preds_history.shape[-1] == 1:
        test_preds_history = test_preds_history.squeeze(-1)

    ensemble_mean_preds = np.mean(test_preds_history, axis=0)
    ensemble_median_preds = np.median(test_preds_history, axis=0)

    # Save ensemble prediction results
    np.save(
        os.path.join(output_dir, "ensemble_mean_preds_test.npy"), ensemble_mean_preds
    )
    np.save(
        os.path.join(output_dir, "ensemble_median_preds_test.npy"),
        ensemble_median_preds,
    )

    # Get test set true labels (from the last fold)
    true_labels_test = np.load(
        os.path.join(output_dir, f"true_labels_test_fold{n_splits}.npy")
    )

    # Verify consistency of test set labels across all folds
    print("Verifying test set label consistency...")
    all_test_labels = []
    for i in range(n_splits):
        fold_labels = np.load(
            os.path.join(output_dir, f"true_labels_test_fold{i+1}.npy")
        )
        all_test_labels.append(fold_labels)
        print(f"  Fold {i+1} test set label shape: {fold_labels.shape}")

    # Check if labels are consistent
    labels_consistent = all(
        np.array_equal(all_test_labels[0], labels) for labels in all_test_labels[1:]
    )
    if labels_consistent:
        print("  ✅ Test set labels are consistent across all folds")
    else:
        print(
            "  [WARNING] Test set labels are inconsistent across folds, which may degrade ensemble performance"
        )
        # Use labels from the first fold as reference
        true_labels_test = all_test_labels[0]

    # Calculate performance metrics for ensemble predictions
    ensemble_mean_mse = mean_squared_error(true_labels_test, ensemble_mean_preds)
    ensemble_mean_r2 = r2_score(true_labels_test, ensemble_mean_preds)
    ensemble_median_mse = mean_squared_error(true_labels_test, ensemble_median_preds)
    ensemble_median_r2 = r2_score(true_labels_test, ensemble_median_preds)

    print("\nEnsemble prediction performance metrics:")
    print(f"  Mean ensemble - MSE: {ensemble_mean_mse:.4f}, R²: {ensemble_mean_r2:.4f}")
    print(
        f"  Median ensemble - MSE: {ensemble_median_mse:.4f}, R²: {ensemble_median_r2:.4f}"
    )

    # Calculate performance for each fold
    fold_performances = []
    for i in range(n_splits):
        fold_mse = mean_squared_error(true_labels_test, test_preds_history[i])
        fold_r2 = r2_score(true_labels_test, test_preds_history[i])
        fold_performances.append((fold_mse, fold_r2))
        print(f"  Fold {i+1} - MSE: {fold_mse:.4f}, R²: {fold_r2:.4f}")

    # Calculate average performance of single folds
    single_fold_mse = np.mean([perf[0] for perf in fold_performances])
    single_fold_r2 = np.mean([perf[1] for perf in fold_performances])
    print(
        f"  Average single fold - MSE: {single_fold_mse:.4f}, R²: {single_fold_r2:.4f}"
    )

    # Find best single fold performance
    best_fold_idx = np.argmax([perf[1] for perf in fold_performances])
    best_fold_r2 = fold_performances[best_fold_idx][1]
    print(f"  Best single fold (Fold {best_fold_idx+1}) - R²: {best_fold_r2:.4f}")

    # Check if ensemble learning is effective
    print("\nEnsemble learning effectiveness analysis:")
    if ensemble_mean_r2 > single_fold_r2:
        print(
            f"  [OK] Mean ensemble is effective! Improved R² by {ensemble_mean_r2 - single_fold_r2:.4f} compared to average single fold"
        )
    else:
        print(
            f"  [WARNING] Mean ensemble has no obvious effect, R² is {single_fold_r2 - ensemble_mean_r2:.4f} lower than average single fold"
        )

    if ensemble_mean_r2 > best_fold_r2:
        print(
            f"  [OK] Mean ensemble is effective! Improved R² by {ensemble_mean_r2 - best_fold_r2:.4f} compared to best single fold"
        )
    else:
        print(
            f"  [WARNING] Mean ensemble is worse than best single fold, R² is {best_fold_r2 - ensemble_mean_r2:.4f} lower"
        )

    # Try weighted ensemble
    print("\nTrying weighted ensemble...")
    # Calculate weights based on each fold's performance
    fold_weights = np.array([perf[1] for perf in fold_performances])  # Use R² as weight
    fold_weights = fold_weights / np.sum(fold_weights)  # Normalization
    print(f"  Fold weights: {fold_weights}")

    weighted_preds = np.average(test_preds_history, axis=0, weights=fold_weights)
    weighted_mse = mean_squared_error(true_labels_test, weighted_preds)
    weighted_r2 = r2_score(true_labels_test, weighted_preds)
    print(f"  Weighted ensemble - MSE: {weighted_mse:.4f}, R²: {weighted_r2:.4f}")

    if weighted_r2 > ensemble_mean_r2:
        print(
            f"  [OK] Weighted ensemble improved R² by {weighted_r2 - ensemble_mean_r2:.4f} compared to simple mean ensemble"
        )
        # Save weighted ensemble results
        np.save(
            os.path.join(output_dir, "ensemble_weighted_preds_test.npy"), weighted_preds
        )

    np.save(os.path.join(output_dir, "ensemble_true_labels_test.npy"), true_labels_test)

    # Generate visualization plots
    print("Generating visualization plots...")

    # 1. Ensemble prediction parity plot
    plt.figure(figsize=(8, 6))
    plt.scatter(true_labels_test, ensemble_mean_preds, alpha=0.6)
    plt.plot(
        [true_labels_test.min(), true_labels_test.max()],
        [true_labels_test.min(), true_labels_test.max()],
        "r--",
        lw=2,
    )
    plt.xlabel("True Values")
    plt.ylabel("Predicted Values")
    plt.title("Ensemble Parity Plot")
    plt.savefig(
        os.path.join(output_dir, "ensemble_parity_plot.png"),
        dpi=300,
        bbox_inches="tight",
    )
    plt.close()

    # 2. Ensemble prediction violin plot
    plt.figure(figsize=(10, 6))
    data_to_plot = [true_labels_test, ensemble_mean_preds]
    plt.violinplot(data_to_plot, positions=[1, 2], showmeans=True, showmedians=True)
    plt.xticks([1, 2], ["True Values", "Predicted Values"])
    plt.ylabel("Values")
    plt.title("Ensemble Violin Plot")
    plt.savefig(
        os.path.join(output_dir, "ensemble_violin_plot.png"),
        dpi=300,
        bbox_inches="tight",
    )
    plt.close()

    # 3. Parity plot for each fold
    for fold in range(n_splits):
        fold_preds = np.load(os.path.join(output_dir, f"preds_test_fold{fold+1}.npy"))
        fold_true = np.load(
            os.path.join(output_dir, f"true_labels_test_fold{fold+1}.npy")
        )

        plt.figure(figsize=(8, 6))
        plt.scatter(fold_true, fold_preds, alpha=0.6)
        plt.plot(
            [fold_true.min(), fold_true.max()],
            [fold_true.min(), fold_true.max()],
            "r--",
            lw=2,
        )
        plt.xlabel("True Values")
        plt.ylabel("Predicted Values")
        plt.title(f"Fold {fold+1} Parity Plot")
        plt.savefig(
            os.path.join(output_dir, f"parity_plot_fold{fold+1}.png"),
            dpi=300,
            bbox_inches="tight",
        )
        plt.close()

        # 4. Violin plot for each fold
        plt.figure(figsize=(10, 6))
        data_to_plot = [fold_true, fold_preds]
        plt.violinplot(data_to_plot, positions=[1, 2], showmeans=True, showmedians=True)
        plt.xticks([1, 2], ["True Values", "Predicted Values"])
        plt.ylabel("Values")
        plt.title(f"Fold {fold+1} Violin Plot")
        plt.savefig(
            os.path.join(output_dir, f"violin_plot_fold{fold+1}.png"),
            dpi=300,
            bbox_inches="tight",
        )
        plt.close()

    print("Ensemble prediction results and visualization plots saved")


def evaluate(cfg):
    """
    Complete evaluation process, including model loading, inference, metric calculation, visualization, and ensemble prediction
    """
    import matplotlib.pyplot as plt
    from sklearn.model_selection import StratifiedGroupKFold

    set_seed(cfg.seed)
    device = device2str(cfg.device)

    # Check GPU availability
    if "gpu" in device:
        if not paddle.device.cuda.device_count():
            print(
                "Warning: Configured for GPU evaluation but no GPU detected, using CPU instead"
            )
            device = "cpu"
        else:
            print(f"Using GPU device for evaluation: {device}")
            paddle.set_device(device)

    n_splits = cfg.train.n_splits
    output_dir = cfg.output_dir
    os.makedirs(output_dir, exist_ok=True)

    # Load data
    train_val_dataset = make_dataset(cfg.data.train_path, N=cfg.data.N, device=device)
    test_dataset = make_dataset(cfg.data.test_path, N=cfg.data.N, device=device)

    # Define offline transforms (for inference)
    offline_transforms = paddle.vision.transforms.Compose(
        [
            paddle.vision.transforms.CenterCrop(size=224),
            paddle.vision.transforms.Normalize(
                mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]
            ),
        ]
    )

    kf = StratifiedGroupKFold(n_splits=n_splits)
    uts_label = [it[1][0] for it in train_val_dataset]
    sample_id = [it[1][1] for it in train_val_dataset]

    # Store results for all folds
    train_mse_all_fold = []
    val_mse_all_fold = []
    test_mse_all_fold = []
    train_rsquared_all_fold = []
    val_rsquared_all_fold = []
    test_rsquared_all_fold = []
    test_preds_history = []

    for fold, (train_index, val_index) in enumerate(
        kf.split(train_val_dataset, y=uts_label, groups=sample_id)
    ):
        print(f"Fold {fold + 1}/{n_splits}")
        set_seed(cfg.seed)

        # Prepare filenames for saving prediction results
        output_train_file = os.path.join(output_dir, f"preds_train_fold{fold + 1}.npy")
        output_val_file = os.path.join(output_dir, f"preds_val_fold{fold + 1}.npy")
        output_test_file = os.path.join(output_dir, f"preds_test_fold{fold + 1}.npy")
        output_unique_groups_file = os.path.join(
            output_dir, f"unique_val_groups_fold_{fold + 1}.npy"
        )
        output_sample_id_file = os.path.join(
            output_dir, f"unique_sample_id_fold_{fold + 1}.npy"
        )

        # Check if saved results already exist
        if (
            os.path.exists(output_train_file)
            and os.path.exists(output_val_file)
            and os.path.exists(output_test_file)
        ):
            print("Loading saved outputs for this fold.")
            preds_train = np.load(output_train_file)
            true_labels_train = np.load(
                output_train_file.replace("preds", "true_labels")
            )
            preds_val = np.load(output_val_file)
            true_labels_val = np.load(output_val_file.replace("preds", "true_labels"))
            preds_test = np.load(output_test_file)
            true_labels_test = np.load(output_test_file.replace("preds", "true_labels"))

            test_preds_history.append(preds_test)

            # Load group information
            unique_val_groups = np.load(output_unique_groups_file, allow_pickle=True)
            unique_sample_id = np.load(output_sample_id_file, allow_pickle=True)
            print(f"Loaded unique validation groups: {unique_val_groups}")
            print(f"Loaded unique sample IDs: {unique_sample_id}")

            true_labels_val_flat = true_labels_val
            unique_true_labels_val = sorted(set(true_labels_val_flat))
            print(
                f"Validation groups for fold {fold+1} contains unique UTS: {unique_true_labels_val}"
            )

            # Load sample IDs
            train_samples_id = np.load(output_train_file.replace("preds", "sample_ids"))
            val_samples_id = np.load(output_val_file.replace("preds", "sample_ids"))
            test_samples_id = np.load(output_test_file.replace("preds", "sample_ids"))

        else:
            print("Computing new predictions for this fold.")
            # Create training and validation datasets
            train_dataset = paddle.io.Subset(train_val_dataset, train_index)
            val_dataset = paddle.io.Subset(train_val_dataset, val_index)

            # Create data loaders
            train_loader = paddle.io.DataLoader(
                train_dataset, batch_size=32, shuffle=False, num_workers=0
            )
            val_loader = paddle.io.DataLoader(
                val_dataset, batch_size=128, shuffle=False, num_workers=0
            )
            test_loader = paddle.io.DataLoader(
                test_dataset, batch_size=128, shuffle=False, num_workers=0
            )

            # Load model
            model = paddle.load(
                f"./resnet18-v5-finetune/resnet18-v5-fold{fold + 1}.pdparams"
            )
            model.eval()
            model.to(device)

            true_labels_train, preds_train = [], []
            true_labels_val, preds_val = [], []
            true_labels_test, preds_test = [], []

            # Store group information
            train_groups_fold, train_samples_id = [], []
            val_groups_fold, val_samples_id = [], []
            test_groups_fold, test_samples_id = [], []

            with paddle.no_grad():
                # Training set inference
                for images, groups, labels in train_loader:
                    images = offline_transforms(images)
                    outputs = model(images)
                    true_labels_train.append(labels.numpy())
                    preds_train.append(outputs.numpy())
                    train_groups_fold.extend(groups[0].numpy())
                    train_samples_id.extend(groups[1].numpy())

                # Validation set inference
                for images, groups, labels in val_loader:
                    images = offline_transforms(images)
                    outputs = model(images)
                    true_labels_val.append(labels.numpy())
                    preds_val.append(outputs.numpy())
                    val_groups_fold.extend(groups[0].numpy())
                    val_samples_id.extend(groups[1].numpy())

                # Test set inference
                for images, groups, labels in test_loader:
                    images = offline_transforms(images)
                    outputs = model(images)
                    true_labels_test.append(labels.numpy())
                    preds_test.append(outputs.numpy())
                    test_groups_fold.extend(groups[0].numpy())
                    test_samples_id.extend(groups[1].numpy())

            # Flatten results
            true_labels_train = np.concatenate(true_labels_train)
            preds_train = np.concatenate(preds_train)
            true_labels_val = np.concatenate(true_labels_val)
            preds_val = np.concatenate(preds_val)
            true_labels_test = np.concatenate(true_labels_test)
            preds_test = np.concatenate(preds_test)

            test_preds_history.append(preds_test)

            unique_val_groups = sorted(set(val_groups_fold))
            print(
                f"Validation groups for fold {fold+1} contains UTS groups: {unique_val_groups}"
            )

            unique_sample_id = sorted(set(val_samples_id))
            print(
                f"Validation groups for fold {fold+1} contains sample ID: {unique_sample_id}"
            )

            true_labels_val_flat = true_labels_val
            unique_true_labels_val = sorted(set(true_labels_val_flat))
            print(
                f"Validation groups for fold {fold+1} contains unique UTS: {unique_true_labels_val}"
            )

            # Save prediction results
            np.save(output_train_file, preds_train)
            np.save(output_val_file, preds_val)
            np.save(output_test_file, preds_test)
            np.save(
                output_train_file.replace("preds", "true_labels"), true_labels_train
            )
            np.save(output_val_file.replace("preds", "true_labels"), true_labels_val)
            np.save(output_test_file.replace("preds", "true_labels"), true_labels_test)
            np.save(output_unique_groups_file, unique_val_groups)
            np.save(output_sample_id_file, unique_sample_id)
            np.save(output_train_file.replace("preds", "sample_ids"), train_samples_id)
            np.save(output_val_file.replace("preds", "sample_ids"), val_samples_id)
            np.save(output_test_file.replace("preds", "sample_ids"), test_samples_id)

            print(f"Saved predictions for fold {fold + 1}.")

        # Calculate metrics
        r_squared_train = r2_score(true_labels_train, preds_train)
        mse_train = mean_squared_error(true_labels_train, preds_train)
        r_squared_val = r2_score(true_labels_val, preds_val)
        mse_val = mean_squared_error(true_labels_val, preds_val)
        r_squared_test = r2_score(true_labels_test, preds_test)
        mse_test = mean_squared_error(true_labels_test, preds_test)
        print(f"MSE: Train: {mse_train}, Validation: {mse_val}, Test: {mse_test}")

        # Store metrics
        train_rsquared_all_fold.append(r_squared_train)
        val_rsquared_all_fold.append(r_squared_val)
        test_rsquared_all_fold.append(r_squared_test)
        train_mse_all_fold.append(mse_train)
        val_mse_all_fold.append(mse_val)
        test_mse_all_fold.append(mse_test)

        # Plot parity plot
        fig, ax = plt.subplots(figsize=(8, 6))
        ax.scatter(
            true_labels_train,
            preds_train,
            s=30,
            marker=".",
            alpha=0.6,
            label=f"Train R-squared: {r_squared_train:.4f}",
        )
        ax.scatter(
            true_labels_val,
            preds_val,
            s=30,
            marker="*",
            alpha=0.6,
            label=f"Validation R-squared: {r_squared_val:.4f}",
        )
        ax.scatter(
            true_labels_test,
            preds_test,
            s=30,
            marker="o",
            color="red",
            alpha=0.6,
            label=f"Test R-squared: {r_squared_test:.4f}",
        )
        ax.plot(
            [true_labels_train.min(), true_labels_train.max()],
            [true_labels_train.min(), true_labels_train.max()],
            color="black",
            linestyle="--",
            lw=2,
            label="Ideal fit",
        )
        ax.set_xlabel("True UTS (MPa)", fontsize=14)
        ax.set_ylabel("Predicted UTS (MPa)", fontsize=14)
        ax.set_aspect("equal")
        ax.set_title(f"Fold {fold + 1} Parity Plot", fontsize=16)
        ax.legend(fontsize=12)
        ax.grid(True, alpha=0.3)
        plt.tight_layout()
        plt.savefig(
            os.path.join(output_dir, f"parity_plot_fold{fold+1}.png"),
            dpi=300,
            bbox_inches="tight",
        )
        plt.close()

        # Plot complex violin plot (similar to the style in the image)
        fig, ax = plt.subplots(figsize=(10, 8))

        # Prepare data
        train_label_added = False
        val_label_added = False
        test_label_added = False

        # Ensure consistent array lengths
        min_train_length = min(
            len(preds_train), len(train_samples_id), len(true_labels_train)
        )
        preds_train_aligned = preds_train[:min_train_length]
        train_samples_id_aligned = train_samples_id[:min_train_length]
        true_labels_train_aligned = true_labels_train[:min_train_length]

        # Training set violin plot
        for i, label in enumerate(np.unique(train_samples_id_aligned)):
            mask = train_samples_id_aligned == label
            preds_for_label = preds_train_aligned[mask]
            true_for_label = true_labels_train_aligned[mask]
            parts = ax.violinplot(
                preds_for_label,
                positions=[np.mean(true_for_label)],
                showmeans=False,
                showmedians=True,
            )
            for pc in parts["bodies"]:
                pc.set_facecolor("tab:blue")
                pc.set_edgecolor("black")
                pc.set_alpha(0.5)
            parts["cmedians"].set_color("tab:blue")
            parts["cmins"].set_color("tab:blue")
            parts["cmaxes"].set_color("tab:blue")
            if not train_label_added:
                ax.plot(
                    true_for_label,
                    preds_for_label,
                    "o",
                    color="tab:blue",
                    markersize=4,
                    label=f"Train $R^2$: {r_squared_train:.4f}",
                    alpha=0.6,
                )
                train_label_added = True
            else:
                ax.plot(
                    true_for_label,
                    preds_for_label,
                    "o",
                    color="tab:blue",
                    markersize=4,
                    alpha=0.6,
                )

        # Validation set violin plot
        for i, label in enumerate(np.unique(val_samples_id)):
            mask = val_samples_id == label
            preds_for_label = preds_val[mask]
            true_for_label = true_labels_val[mask]
            parts = ax.violinplot(
                preds_for_label,
                positions=[np.mean(true_for_label)],
                showmeans=False,
                showmedians=True,
            )
            for pc in parts["bodies"]:
                pc.set_facecolor("tab:orange")
                pc.set_edgecolor("black")
                pc.set_alpha(0.5)
            parts["cmedians"].set_color("tab:orange")
            parts["cmins"].set_color("tab:orange")
            parts["cmaxes"].set_color("tab:orange")
            if not val_label_added:
                ax.plot(
                    true_for_label,
                    preds_for_label,
                    "d",
                    color="tab:orange",
                    markersize=4,
                    label=f"Val $R^2$: {r_squared_val:.4f}",
                    alpha=0.6,
                )
                val_label_added = True
            else:
                ax.plot(
                    true_for_label,
                    preds_for_label,
                    "d",
                    color="tab:orange",
                    markersize=4,
                    alpha=0.6,
                )

        # Test set violin plot
        for i, label in enumerate(np.unique(test_samples_id)):
            mask = test_samples_id == label
            preds_for_label = preds_test[mask]
            true_for_label = true_labels_test[mask]
            parts = ax.violinplot(
                preds_for_label,
                positions=[np.mean(true_for_label)],
                showmeans=False,
                showmedians=True,
            )
            for pc in parts["bodies"]:
                pc.set_facecolor("tab:red")
                pc.set_edgecolor("black")
                pc.set_alpha(0.5)
            parts["cmedians"].set_color("tab:red")
            parts["cmins"].set_color("tab:red")
            parts["cmaxes"].set_color("tab:red")
            if not test_label_added:
                ax.plot(
                    true_for_label,
                    preds_for_label,
                    "x",
                    color="tab:red",
                    markersize=4,
                    label=f"Test $R^2$: {r_squared_test:.4f}",
                    alpha=0.6,
                )
                test_label_added = True
            else:
                ax.plot(
                    true_for_label,
                    preds_for_label,
                    "x",
                    color="tab:red",
                    markersize=4,
                    alpha=0.6,
                )

        # Add ideal fit line
        ax.plot(
            [true_labels_train_aligned.min(), true_labels_train_aligned.max()],
            [true_labels_train_aligned.min(), true_labels_train_aligned.max()],
            label="Ideal fit",
            color="black",
            linestyle="--",
        )
        ax.legend(prop={"size": 11})
        ax.set_xlabel("True UTS (MPa)", fontsize=18)
        ax.set_ylabel("Predicted UTS (MPa)", fontsize=18)
        ax.tick_params(axis="x", direction="in", top=True, length=3, width=1)
        ax.tick_params(axis="y", direction="in", right=True, length=3, width=1)
        ax.set_title(f"Fold {fold+1} Parity Violin Plot", fontsize=16)
        plt.xticks(np.arange(0, 5.2, 1), fontsize=16)
        plt.yticks(np.arange(0, 5.2, 1), fontsize=16)
        plt.tight_layout()
        plt.savefig(
            os.path.join(output_dir, f"violin_plot_fold{fold+1}.png"),
            dpi=300,
            bbox_inches="tight",
        )
        plt.close()

    # Final statistical results
    print("\nFinal Statistics Across All Folds:")
    print(
        f"Train MSE: {np.mean(train_mse_all_fold):.4f} ± {np.std(train_mse_all_fold):.4f}"
    )
    print(
        f"Train R-squared: {np.mean(train_rsquared_all_fold):.4f} ± {np.std(train_rsquared_all_fold):.4f}"
    )
    print(
        f"Validation MSE: {np.mean(val_mse_all_fold):.4f} ± {np.std(val_mse_all_fold):.4f}"
    )
    print(
        f"Validation R-squared: {np.mean(val_rsquared_all_fold):.4f} ± {np.std(val_rsquared_all_fold):.4f}"
    )
    print(
        f"Test MSE: {np.mean(test_mse_all_fold):.4f} ± {np.std(test_mse_all_fold):.4f}"
    )
    print(
        f"Test R-squared: {np.mean(test_rsquared_all_fold):.4f} ± {np.std(test_rsquared_all_fold):.4f}"
    )

    # Ensemble Learning
    print("\nEnsemble Learning for Test Data:")
    test_preds_history = np.array(test_preds_history)
    print(f"Ensemble prediction shape: {test_preds_history.shape}")

    # Calculate prediction variance for each fold to evaluate ensemble diversity
    pred_variance = np.var(test_preds_history, axis=0)
    print(
        f"Prediction variance statistics: Mean={np.mean(pred_variance):.4f}, Std={np.std(pred_variance):.4f}"
    )

    # Calculate median and mean predictions
    # Ensure correct data shape, remove extra dimensions
    if test_preds_history.ndim == 3 and test_preds_history.shape[-1] == 1:
        test_preds_history = test_preds_history.squeeze(-1)

    median_preds_test = np.median(test_preds_history, axis=0)
    mean_preds_test = np.mean(test_preds_history, axis=0)

    # Load test set true labels (using results from the last fold)
    true_labels_test = np.load(
        os.path.join(output_dir, f"true_labels_test_fold{n_splits}.npy")
    )

    # Calculate ensemble metrics
    median_test_mse = np.mean((median_preds_test - true_labels_test) ** 2)
    median_test_r2 = r2_score(true_labels_test, median_preds_test)
    mean_test_mse = np.mean((mean_preds_test - true_labels_test) ** 2)
    mean_test_r2 = r2_score(true_labels_test, mean_preds_test)

    print(
        f"Median Test MSE: {median_test_mse:.4f}, Median Test R-squared: {median_test_r2:.4f}"
    )
    print(
        f"Mean Test MSE: {mean_test_mse:.4f}, Mean Test R-squared: {mean_test_r2:.4f}"
    )

    # Plot parity plot for ensemble predictions
    fig, ax = plt.subplots(figsize=(8, 6))
    ax.scatter(
        true_labels_test,
        median_preds_test,
        s=30,
        marker="o",
        alpha=0.6,
        label=f"Median R-squared: {median_test_r2:.4f}",
    )
    ax.scatter(
        true_labels_test,
        mean_preds_test,
        s=30,
        marker="x",
        alpha=0.6,
        label=f"Mean R-squared: {mean_test_r2:.4f}",
    )
    ax.plot(
        [true_labels_test.min(), true_labels_test.max()],
        [true_labels_test.min(), true_labels_test.max()],
        color="black",
        linestyle="--",
        lw=2,
        label="Ideal fit",
    )
    ax.set_xlabel("True UTS (MPa)", fontsize=14)
    ax.set_ylabel("Predicted UTS (MPa)", fontsize=14)
    ax.set_aspect("equal")
    ax.set_title("Test Data Parity Plot (Ensemble Predictions)", fontsize=16)
    ax.legend(fontsize=12)
    ax.grid(True, alpha=0.3)
    plt.tight_layout()
    plt.savefig(
        os.path.join(output_dir, "ensemble_parity_plot.png"),
        dpi=300,
        bbox_inches="tight",
    )
    plt.close()

    # Plot complex violin plot for ensemble predictions
    fig, ax = plt.subplots(figsize=(10, 8))

    # Create violin plot for each true value range
    test_label_added = False
    for i, label in enumerate(np.unique(true_labels_test)):
        mask = true_labels_test == label
        preds_for_label = mean_preds_test[mask]
        parts = ax.violinplot(
            preds_for_label, positions=[label], showmeans=False, showmedians=True
        )
        for pc in parts["bodies"]:
            pc.set_facecolor("tab:red")
            pc.set_edgecolor("black")
            pc.set_alpha(0.5)
        parts["cmedians"].set_color("tab:red")
        parts["cmins"].set_color("tab:red")
        parts["cmaxes"].set_color("tab:red")
        if not test_label_added:
            ax.plot(
                [label] * len(preds_for_label),
                preds_for_label,
                "rx",
                markersize=4,
                label=f"Test $R^2$: {mean_test_r2:.4f}",
                alpha=0.6,
            )
            test_label_added = True
        else:
            ax.plot(
                [label] * len(preds_for_label),
                preds_for_label,
                "rx",
                markersize=4,
                alpha=0.6,
            )

    # Add ideal fit line
    ax.plot(
        [true_labels_test.min(), true_labels_test.max() + 0.4],
        [true_labels_test.min(), true_labels_test.max() + 0.4],
        label="Ideal fit",
        color="black",
        linestyle="--",
    )
    ax.set_xlabel("True UTS (MPa)", fontsize=18)
    ax.set_ylabel("Predicted UTS (MPa)", fontsize=18)
    ax.tick_params(axis="x", direction="in", top=True, length=3, width=1)
    ax.tick_params(axis="y", direction="in", right=True, length=3, width=1)
    ax.legend(loc="upper left", prop={"size": 12})
    plt.xticks(np.arange(0, 4.2, 1), fontsize=16)
    plt.yticks(np.arange(0, 4.2, 1), fontsize=16)
    ax.set_title("Ensemble Parity Violin Plot", fontsize=16)
    plt.tight_layout()
    plt.savefig(
        os.path.join(output_dir, "ensemble_violin_plot.png"),
        dpi=300,
        bbox_inches="tight",
    )
    plt.close()

    # Save ensemble prediction results
    np.save(
        os.path.join(output_dir, "ensemble_median_preds_test.npy"), median_preds_test
    )
    np.save(os.path.join(output_dir, "ensemble_mean_preds_test.npy"), mean_preds_test)
    np.save(os.path.join(output_dir, "ensemble_true_labels_test.npy"), true_labels_test)

    print(f"\nAll results saved to {output_dir}")


@hydra.main(version_base=None, config_path="./conf", config_name="resnet.yaml")
def main(cfg: DictConfig):
    if cfg.mode == "train":
        train(cfg)
    elif cfg.mode == "eval":
        evaluate(cfg)
    else:
        raise ValueError(f"cfg.mode should in ['train', 'eval'], but got '{cfg.mode}'")


if __name__ == "__main__":
    main()

参考文献