[Docs] Refine API reference. (#774)

* [Docs] Refine API reference

* Add PoolFormer

.gitignore

@@ -69,10 +69,12 @@ docs/en/_build/
 docs/en/_model_zoo.rst
 docs/en/modelzoo_statistics.md
 docs/en/papers/
+docs/en/api/generated/
 docs/zh_CN/_build/
 docs/zh_CN/_model_zoo.rst
 docs/zh_CN/modelzoo_statistics.md
 docs/zh_CN/papers/
+docs/zh_CN/api/generated/
 
 # PyBuilder
 target/

docs/en/_static/css/readthedocs.css

@@ -14,3 +14,7 @@ article.pytorch-article .section :not(dt) > code {
   background-color: #f3f4f7;
   border-radius: 5px;
 }
+
+table.colwidths-auto td {
+  width: 50%
+}

docs/en/_templates/classtemplate.rst

@@ -0,0 +1,14 @@
+.. role:: hidden
+    :class: hidden-section
+.. currentmodule:: {{ module }}
+
+
+{{ name | underline}}
+
+.. autoclass:: {{ name }}
+    :members:
+
+
+..
+  autogenerated from source/_templates/classtemplate.rst
+  note it does not have :inherited-members:

docs/en/api.rst

@@ -1,68 +0,0 @@
-mmcls.apis
--------------
-.. automodule:: mmcls.apis
-    :members:
-
-mmcls.core
--------------
-
-evaluation
-^^^^^^^^^^
-.. automodule:: mmcls.core.evaluation
-    :members:
-
-mmcls.models
----------------
-
-models
-^^^^^^
-.. automodule:: mmcls.models
-    :members:
-
-classifiers
-^^^^^^^^^^^
-.. automodule:: mmcls.models.classifiers
-    :members:
-
-backbones
-^^^^^^^^^^
-.. automodule:: mmcls.models.backbones
-    :members:
-
-necks
-^^^^^^
-.. automodule:: mmcls.models.necks
-    :members:
-
-heads
-^^^^^^
-.. automodule:: mmcls.models.heads
-    :members:
-
-losses
-^^^^^^
-.. automodule:: mmcls.models.losses
-    :members:
-
-utils
-^^^^^^
-.. automodule:: mmcls.models.utils
-    :members:
-
-mmcls.datasets
------------------
-
-datasets
-^^^^^^^^
-.. automodule:: mmcls.datasets
-    :members:
-
-pipelines
-^^^^^^^^^
-.. automodule:: mmcls.datasets.pipelines
-    :members:
-
-mmcls.utils
---------------
-.. automodule:: mmcls.utils
-    :members:

docs/en/api/apis.rst

@@ -0,0 +1,45 @@
+.. role:: hidden
+    :class: hidden-section
+
+mmcls.apis
+===================================
+
+These are some high-level APIs for classification tasks.
+
+.. contents:: mmcls.apis
+   :depth: 2
+   :local:
+   :backlinks: top
+
+.. currentmodule:: mmcls.apis
+
+Train
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+
+   init_random_seed
+   set_random_seed
+   train_model
+
+Test
+------------------
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+
+   single_gpu_test
+   multi_gpu_test
+
+Inference
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+
+   init_model
+   inference_model
+   show_result_pyplot

docs/en/api/core.rst

@@ -0,0 +1,61 @@
+.. role:: hidden
+    :class: hidden-section
+
+mmcls.core
+===================================
+
+This package includes some runtime components. These components are useful in
+classification tasks but not supported by MMCV yet.
+
+.. note::
+
+   Some components may be moved to MMCV in the future.
+
+.. contents:: mmcls.core
+   :depth: 2
+   :local:
+   :backlinks: top
+
+.. currentmodule:: mmcls.core
+
+Evaluation
+------------------
+
+Evaluation metrics calculation functions
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+
+   precision
+   recall
+   f1_score
+   precision_recall_f1
+   average_precision
+   mAP
+   support
+   average_performance
+   calculate_confusion_matrix
+
+Hook
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   ClassNumCheckHook
+   PreciseBNHook
+   CosineAnnealingCooldownLrUpdaterHook
+
+
+Optimizers
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   Lamb

docs/en/api/datasets.rst

@@ -0,0 +1,56 @@
+.. role:: hidden
+    :class: hidden-section
+
+mmcls.datasets
+===================================
+
+The ``datasets`` package contains several usual datasets for image classification tasks and some dataset wrappers.
+
+.. currentmodule:: mmcls.datasets
+
+Custom Dataset
+--------------
+
+.. autoclass:: CustomDataset
+
+ImageNet
+--------
+
+.. autoclass:: ImageNet
+
+.. autoclass:: ImageNet21k
+
+CIFAR
+-----
+
+.. autoclass:: CIFAR10
+
+.. autoclass:: CIFAR100
+
+MNIST
+-----
+
+.. autoclass:: MNIST
+
+.. autoclass:: FashionMNIST
+
+VOC
+---
+
+.. autoclass:: VOC
+
+Base classes
+------------
+
+.. autoclass:: BaseDataset
+
+.. autoclass:: MultiLabelDataset
+
+Dataset Wrappers
+----------------
+
+.. autoclass:: ConcatDataset
+
+.. autoclass:: RepeatDataset
+
+.. autoclass:: ClassBalancedDataset

docs/en/api/models.rst

@@ -0,0 +1,137 @@
+.. role:: hidden
+    :class: hidden-section
+
+mmcls.models
+===================================
+
+The ``models`` package contains several sub-packages for addressing the different components of a model.
+
+- :ref:`classifiers`: The top-level module which defines the whole process of a classification model.
+- :ref:`backbones`: Usually a feature extraction network, e.g., ResNet, MobileNet.
+- :ref:`necks`: The component between backbones and heads, e.g., GlobalAveragePooling.
+- :ref:`heads`: The component for specific tasks. In MMClassification, we provides heads for classification.
+- :ref:`losses`: Loss functions.
+
+.. currentmodule:: mmcls.models
+
+.. autosummary::
+    :toctree: generated
+    :nosignatures:
+
+    build_classifier
+    build_backbone
+    build_neck
+    build_head
+    build_loss
+
+.. _classifiers:
+
+Classifier
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   BaseClassifier
+   ImageClassifier
+
+.. _backbones:
+
+Backbones
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   AlexNet
+   CSPDarkNet
+   CSPNet
+   CSPResNeXt
+   CSPResNet
+   Conformer
+   ConvMixer
+   ConvNeXt
+   DistilledVisionTransformer
+   EfficientNet
+   HRNet
+   LeNet5
+   MlpMixer
+   MobileNetV2
+   MobileNetV3
+   PCPVT
+   PoolFormer
+   RegNet
+   RepMLPNet
+   RepVGG
+   Res2Net
+   ResNeSt
+   ResNeXt
+   ResNet
+   ResNetV1c
+   ResNetV1d
+   ResNet_CIFAR
+   SEResNeXt
+   SEResNet
+   SVT
+   ShuffleNetV1
+   ShuffleNetV2
+   SwinTransformer
+   T2T_ViT
+   TIMMBackbone
+   TNT
+   VGG
+   VisionTransformer
+
+.. _necks:
+
+Necks
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   GlobalAveragePooling
+   GeneralizedMeanPooling
+   HRFuseScales
+
+.. _heads:
+
+Heads
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   ClsHead
+   LinearClsHead
+   StackedLinearClsHead
+   MultiLabelClsHead
+   MultiLabelLinearClsHead
+   VisionTransformerClsHead
+   DeiTClsHead
+   ConformerHead
+
+.. _losses:
+
+Losses
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   Accuracy
+   AsymmetricLoss
+   CrossEntropyLoss
+   LabelSmoothLoss
+   FocalLoss
+   SeesawLoss

docs/en/api/models.utils.augment.rst

@@ -0,0 +1,35 @@
+.. role:: hidden
+    :class: hidden-section
+
+Batch Augmentation
+===================================
+
+Batch augmentation is the augmentation which involve multiple samples, such as Mixup and CutMix.
+
+In MMClassification, these batch augmentation is used as a part of :ref:`classifiers`. A typical usage is as below:
+
+.. code-block:: python
+
+   model = dict(
+       backbone = ...,
+       neck = ...,
+       head = ...,
+       train_cfg=dict(augments=[
+           dict(type='BatchMixup', alpha=0.8, prob=0.5, num_classes=num_classes),
+           dict(type='BatchCutMix', alpha=1.0, prob=0.5, num_classes=num_classes),
+       ]))
+   )
+
+.. currentmodule:: mmcls.models.utils.augment
+
+Mixup
+-----
+.. autoclass:: BatchMixupLayer
+
+CutMix
+------
+.. autoclass:: BatchCutMixLayer
+
+ResizeMix
+---------
+.. autoclass:: BatchResizeMixLayer

docs/en/api/models.utils.rst

@@ -0,0 +1,50 @@
+.. role:: hidden
+    :class: hidden-section
+
+mmcls.models.utils
+===================================
+
+This package includes some helper functions and common components used in various networks.
+
+.. contents:: mmcls.models.utils
+   :depth: 2
+   :local:
+   :backlinks: top
+
+.. currentmodule:: mmcls.models.utils
+
+Common Components
+------------------
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   InvertedResidual
+   SELayer
+   ShiftWindowMSA
+   MultiheadAttention
+   ConditionalPositionEncoding
+
+Helper Functions
+------------------
+
+channel_shuffle
+^^^^^^^^^^^^^^^
+.. autofunction:: channel_shuffle
+
+make_divisible
+^^^^^^^^^^^^^^
+.. autofunction:: make_divisible
+
+to_ntuple
+^^^^^^^^^^^^^^
+.. autofunction:: to_ntuple
+.. autofunction:: to_2tuple
+.. autofunction:: to_3tuple
+.. autofunction:: to_4tuple
+
+is_tracing
+^^^^^^^^^^^^^^
+.. autofunction:: is_tracing

docs/en/api/transforms.rst

@@ -0,0 +1,171 @@
+.. role:: hidden
+    :class: hidden-section
+
+Data Transformations
+***********************************
+
+In MMClassification, the data preparation and the dataset is decomposed. The
+datasets only define how to get samples' basic information from the file
+system. These basic information includes the ground-truth label and raw images
+data / the paths of images.
+
+To prepare the inputs data, we need to do some transformations on these basic
+information. These transformations includes loading, preprocessing and
+formatting. And a series of data transformations makes up a data pipeline.
+Therefore, you can find the a ``pipeline`` argument in the configs of dataset,
+for example:
+
+.. code:: python
+
+    img_norm_cfg = dict(
+        mean=[123.675, 116.28, 103.53], std=[58.395, 57.12, 57.375], to_rgb=True)
+    train_pipeline = [
+        dict(type='LoadImageFromFile'),
+        dict(type='RandomResizedCrop', size=224),
+        dict(type='RandomFlip', flip_prob=0.5, direction='horizontal'),
+        dict(type='Normalize', **img_norm_cfg),
+        dict(type='ImageToTensor', keys=['img']),
+        dict(type='ToTensor', keys=['gt_label']),
+        dict(type='Collect', keys=['img', 'gt_label'])
+    ]
+    test_pipeline = [
+        dict(type='LoadImageFromFile'),
+        dict(type='Resize', size=256),
+        dict(type='CenterCrop', crop_size=224),
+        dict(type='Normalize', **img_norm_cfg),
+        dict(type='ImageToTensor', keys=['img']),
+        dict(type='Collect', keys=['img'])
+    ]
+
+    data = dict(
+        train=dict(..., pipeline=train_pipeline),
+        val=dict(..., pipeline=test_pipeline),
+        test=dict(..., pipeline=test_pipeline),
+    )
+
+Every item of a pipeline list is one of the following data transformations class. And if you want to add a custom data transformation class, the tutorial :doc:`Custom Data Pipelines </tutorials/data_pipeline>` will help you.
+
+.. contents:: mmcls.datasets.pipelines
+   :depth: 2
+   :local:
+   :backlinks: top
+
+.. currentmodule:: mmcls.datasets.pipelines
+
+Loading
+=======
+
+LoadImageFromFile
+---------------------
+.. autoclass:: LoadImageFromFile
+
+Preprocessing and Augmentation
+==============================
+
+CenterCrop
+---------------------
+.. autoclass:: CenterCrop
+
+Lighting
+---------------------
+.. autoclass:: Lighting
+
+Normalize
+---------------------
+.. autoclass:: Normalize
+
+Pad
+---------------------
+.. autoclass:: Pad
+
+Resize
+---------------------
+.. autoclass:: Resize
+
+RandomCrop
+---------------------
+.. autoclass:: RandomCrop
+
+RandomErasing
+---------------------
+.. autoclass:: RandomErasing
+
+RandomFlip
+---------------------
+.. autoclass:: RandomFlip
+
+RandomGrayscale
+---------------------
+.. autoclass:: RandomGrayscale
+
+RandomResizedCrop
+---------------------
+.. autoclass:: RandomResizedCrop
+
+ColorJitter
+---------------------
+.. autoclass:: ColorJitter
+
+
+Composed Augmentation
+---------------------
+Composed augmentation is a kind of methods which compose a series of data
+augmentation transformations, such as ``AutoAugment`` and ``RandAugment``.
+
+.. autoclass:: AutoAugment
+
+.. autoclass:: RandAugment
+
+In composed augmentation, we need to specify several data transformations or
+several groups of data transformations (The ``policies`` argument) as the
+random sampling space. These data transformations are chosen from the below
+table. In addition, we provide some preset policies in `this folder`_.
+
+.. _this folder: https://github.com/open-mmlab/mmclassification/tree/master/configs/_base_/datasets/pipelines
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+   :template: classtemplate.rst
+
+   AutoContrast
+   Brightness
+   ColorTransform
+   Contrast
+   Cutout
+   Equalize
+   Invert
+   Posterize
+   Rotate
+   Sharpness
+   Shear
+   Solarize
+   SolarizeAdd
+   Translate
+
+Formatting
+==========
+
+Collect
+---------------------
+.. autoclass:: Collect
+
+ImageToTensor
+---------------------
+.. autoclass:: ImageToTensor
+
+ToNumpy
+---------------------
+.. autoclass:: ToNumpy
+
+ToPIL
+---------------------
+.. autoclass:: ToPIL
+
+ToTensor
+---------------------
+.. autoclass:: ToTensor
+
+Transpose
+---------------------
+.. autoclass:: Transpose

docs/en/api/utils.rst

@@ -0,0 +1,23 @@
+.. role:: hidden
+    :class: hidden-section
+
+mmcls.utils
+===================================
+
+These are some useful help function in the ``utils`` package.
+
+.. contents:: mmcls.utils
+   :depth: 1
+   :local:
+   :backlinks: top
+
+.. currentmodule:: mmcls.utils
+
+.. autosummary::
+   :toctree: generated
+   :nosignatures:
+
+   collect_env
+   get_root_logger
+   load_json_log
+   setup_multi_processes

docs/en/conf.py

@@ -44,6 +44,8 @@ release = get_version()
 # ones.
 extensions = [
     'sphinx.ext.autodoc',
+    'sphinx.ext.autosummary',
+    'sphinx.ext.intersphinx',
     'sphinx.ext.napoleon',
     'sphinx.ext.viewcode',
     'sphinx_markdown_tables',
@@ -218,6 +220,15 @@ StandaloneHTMLBuilder.supported_image_types = [
 # Ignore >>> when copying code
 copybutton_prompt_text = r'>>> |\.\.\. '
 copybutton_prompt_is_regexp = True
+# Auto-generated header anchors
+myst_heading_anchors = 3
+# Configuration for intersphinx
+intersphinx_mapping = {
+    'python': ('https://docs.python.org/3', None),
+    'numpy': ('https://numpy.org/doc/stable', None),
+    'torch': ('https://pytorch.org/docs/stable/', None),
+    'mmcv': ('https://mmcv.readthedocs.io/en/master/', None),
+}
 
 
 def builder_inited_handler(app):

docs/en/docutils.conf

@@ -0,0 +1,2 @@
+[html writers]
+table_style: colwidths-auto

docs/en/index.rst

@@ -57,9 +57,17 @@ You can switch between Chinese and English documentation in the lower-left corne
 
 
 .. toctree::
+   :maxdepth: 1
    :caption: API Reference
 
-   api.rst
+   mmcls.apis <api/apis>
+   mmcls.core <api/core>
+   mmcls.models <api/models>
+   mmcls.models.utils <api/models.utils>
+   mmcls.datasets <api/datasets>
+   Data Transformations <api/transforms>
+   Batch Augmentation <api/models.utils.augment>
+   mmcls.utils <api/utils>
 
 
 .. toctree::

docs/en/tutorials/config.md

@@ -13,7 +13,7 @@ If you wish to inspect the config file, you may run `python tools/misc/print_con
   - [Ignore some fields in the base configs](#ignore-some-fields-in-the-base-configs)
   - [Use some fields in the base configs](#use-some-fields-in-the-base-configs)
 - [Modify config through script arguments](#modify-config-through-script-arguments)
-- [Import user-defined modules](#import-ser-defined-modules)
+- [Import user-defined modules](#import-user-defined-modules)
 - [FAQ](#faq)
 
 <!-- TOC -->

docs/en/tutorials/data_pipeline.md

@@ -98,6 +98,8 @@ More supported backends can be found in [mmcv.fileio.FileClient](https://github.
 
 - remove: all other keys except for those specified by `keys`
 
+For more information about other data transformation classes, please refer to [Data Transformations](../api/transforms.rst)
+
 ## Extend and use custom pipelines
 
 1. Write a new pipeline in any file, e.g., `my_pipeline.py`, and place it in

docs/en/tutorials/runtime.md

@@ -7,14 +7,8 @@ In this tutorial, we will introduce some methods about how to customize workflow
 - [Customize Workflow](#customize-workflow)
 - [Hooks](#hooks)
   - [Default training hooks](#default-training-hooks)
-    - [CheckpointHook](#checkpointhook)
-    - [LoggerHooks](#loggerhooks)
-    - [EvalHook](#evalhook)
   - [Use other implemented hooks](#use-other-implemented-hooks)
   - [Customize self-implemented hooks](#customize-self-implemented-hooks)
-    - [1. Implement a new hook](#1.-implement-a-new-hook)
-    - [2. Register the new hook](#2.-register-the-new-hook)
-    - [3. Modify the config](#3.-modify-the-config)
 - [FAQ](#faq)
 
 <!-- TOC -->

mmcls/apis/test.py

@@ -18,6 +18,21 @@ def single_gpu_test(model,
                     show=False,
                     out_dir=None,
                     **show_kwargs):
+    """Test model with local single gpu.
+
+    This method tests model with a single gpu and supports showing results.
+
+    Args:
+        model (:obj:`torch.nn.Module`): Model to be tested.
+        data_loader (:obj:`torch.utils.data.DataLoader`): Pytorch data loader.
+        show (bool): Whether to show the test results. Defaults to False.
+        out_dir (str): The output directory of result plots of all samples.
+            Defaults to None, which means not to write output files.
+        **show_kwargs: Any other keyword arguments for showing results.
+
+    Returns:
+        list: The prediction results.
+    """
     model.eval()
     results = []
     dataset = data_loader.dataset

mmcls/apis/train.py

@@ -75,6 +75,28 @@ def train_model(model,
                 timestamp=None,
                 device=None,
                 meta=None):
+    """Train a model.
+
+    This method will build dataloaders, wrap the model and build a runner
+    according to the provided config.
+
+    Args:
+        model (:obj:`torch.nn.Module`): The model to be run.
+        dataset (:obj:`mmcls.datasets.BaseDataset` | List[BaseDataset]):
+            The dataset used to train the model. It can be a single dataset,
+            or a list of dataset with the same length as workflow.
+        cfg (:obj:`mmcv.utils.Config`): The configs of the experiment.
+        distributed (bool): Whether to train the model in a distributed
+            environment. Defaults to False.
+        validate (bool): Whether to do validation with
+            :obj:`mmcv.runner.EvalHook`. Defaults to False.
+        timestamp (str, optional): The timestamp string to auto generate the
+            name of log files. Defaults to None.
+        device (str, optional): TODO
+        meta (dict, optional): A dict records some import information such as
+            environment info and seed, which will be logged in logger hook.
+            Defaults to None.
+    """
     logger = get_root_logger()
 
     # prepare data loaders

mmcls/core/optimizers/lamb.py

@@ -65,13 +65,15 @@ from torch.optim import Optimizer
 
 @OPTIMIZERS.register_module()
 class Lamb(Optimizer):
-    """Implements a pure pytorch variant of FuseLAMB (NvLamb variant) optimizer
+    """A pure pytorch variant of FuseLAMB (NvLamb variant) optimizer.
-    from apex.optimizers.FusedLAMB
-    reference: https://github.com/NVIDIA/DeepLearningExamples/blob/master/
-    PyTorch/LanguageModeling/Transformer-XL/pytorch/lamb.py
 
-    LAMB was proposed in `Large Batch Optimization for Deep Learning: Training
+    This class is copied from `timm`_. The LAMB was proposed in `Large Batch
-    BERT in 76 minutes`_.
+    Optimization for Deep Learning - Training BERT in 76 minutes`_.
+
+    .. _timm:
+        https://github.com/rwightman/pytorch-image-models/blob/master/timm/optim/lamb.py
+    .. _Large Batch Optimization for Deep Learning - Training BERT in 76 minutes:
+        https://arxiv.org/abs/1904.00962
 
     Arguments:
         params (iterable): iterable of parameters to optimize or dicts defining
@@ -89,13 +91,7 @@ class Lamb(Optimizer):
         trust_clip (bool): enable LAMBC trust ratio clipping (default: False)
         always_adapt (boolean, optional): Apply adaptive learning rate to 0.0
             weight decay parameter (default: False)
-
+    """  # noqa: E501
-    .. _Large Batch Optimization for Deep Learning - Training BERT in 76
-        minutes:
-        https://arxiv.org/abs/1904.00962
-    .. _On the Convergence of Adam and Beyond:
-        https://openreview.net/forum?id=ryQu7f-RZ
-    """
 
     def __init__(self,
                  params,

mmcls/datasets/dataset_wrappers.py

@@ -18,7 +18,7 @@ class ConcatDataset(_ConcatDataset):
     add `get_cat_ids` function.
 
     Args:
-        datasets (list[:obj:`Dataset`]): A list of datasets.
+        datasets (list[:obj:`BaseDataset`]): A list of datasets.
         separate_eval (bool): Whether to evaluate the results
             separately if it is used as validation dataset.
             Defaults to True.
@@ -117,7 +117,7 @@ class RepeatDataset(object):
     epochs.
 
     Args:
-        dataset (:obj:`Dataset`): The dataset to be repeated.
+        dataset (:obj:`BaseDataset`): The dataset to be repeated.
         times (int): Repeat times.
     """
 
@@ -157,9 +157,11 @@ class RepeatDataset(object):
 class ClassBalancedDataset(object):
     r"""A wrapper of repeated dataset with repeat factor.
 
-    Suitable for training on class imbalanced datasets like LVIS. Following
+    Suitable for training on class imbalanced datasets like LVIS. Following the
-    the sampling strategy in [#1]_, in each epoch, an image may appear multiple
+    sampling strategy in `this paper`_, in each epoch, an image may appear
-    times based on its "repeat factor".
+    multiple times based on its "repeat factor".
+
+    .. _this paper: https://arxiv.org/pdf/1908.03195.pdf
 
     The repeat factor for an image is a function of the frequency the rarest
     category labeled in that image. The "frequency of category c" in [0, 1]
@@ -184,16 +186,13 @@ class ClassBalancedDataset(object):
         .. math::
             r(I) = \max_{c \in L(I)} r(c)
 
-    References:
-        .. [#1]  https://arxiv.org/pdf/1908.03195.pdf
-
     Args:
-        dataset (:obj:`CustomDataset`): The dataset to be repeated.
+        dataset (:obj:`BaseDataset`): The dataset to be repeated.
         oversample_thr (float): frequency threshold below which data is
-            repeated. For categories with `f_c` >= `oversample_thr`, there is
+            repeated. For categories with ``f_c`` >= ``oversample_thr``, there
-            no oversampling. For categories with `f_c` < `oversample_thr`, the
+            is no oversampling. For categories with ``f_c`` <
-            degree of oversampling following the square-root inverse frequency
+            ``oversample_thr``, the degree of oversampling following the
-            heuristic above.
+            square-root inverse frequency heuristic above.
     """
 
     def __init__(self, dataset, oversample_thr):
@@ -278,7 +277,7 @@ class KFoldDataset:
     and use the fold left to do validation.
 
     Args:
-        dataset (:obj:`CustomDataset`): The dataset to be divided.
+        dataset (:obj:`BaseDataset`): The dataset to be divided.
         fold (int): The fold used to do validation. Defaults to 0.
         num_splits (int): The number of all folds. Defaults to 5.
         test_mode (bool): Use the training dataset or validation dataset.

mmcls/datasets/imagenet.py

@@ -9,8 +9,33 @@ from .custom import CustomDataset
 class ImageNet(CustomDataset):
     """`ImageNet <http://www.image-net.org>`_ Dataset.
 
-    This implementation is modified from
+    The dataset supports two kinds of annotation format. More details can be
-    https://github.com/pytorch/vision/blob/master/torchvision/datasets/imagenet.py
+    found in :class:`CustomDataset`.
+
+    Args:
+        data_prefix (str): The path of data directory.
+        pipeline (Sequence[dict]): A list of dict, where each element
+            represents a operation defined in :mod:`mmcls.datasets.pipelines`.
+            Defaults to an empty tuple.
+        classes (str | Sequence[str], optional): Specify names of classes.
+
+            - If is string, it should be a file path, and the every line of
+              the file is a name of a class.
+            - If is a sequence of string, every item is a name of class.
+            - If is None, use the default ImageNet-1k classes names.
+
+            Defaults to None.
+        ann_file (str, optional): The annotation file. If is string, read
+            samples paths from the ann_file. If is None, find samples in
+            ``data_prefix``. Defaults to None.
+        extensions (Sequence[str]): A sequence of allowed extensions. Defaults
+            to ('.jpg', '.jpeg', '.png', '.ppm', '.bmp', '.pgm', '.tif').
+        test_mode (bool): In train mode or test mode. It's only a mark and
+            won't be used in this class. Defaults to False.
+        file_client_args (dict, optional): Arguments to instantiate a
+            FileClient. See :class:`mmcv.fileio.FileClient` for details.
+            If None, automatically inference from the specified path.
+            Defaults to None.
     """  # noqa: E501
 
     IMG_EXTENSIONS = ('.jpg', '.jpeg', '.png', '.ppm', '.bmp', '.pgm', '.tif')

mmcls/datasets/imagenet21k.py

@@ -31,8 +31,8 @@ class ImageNet21k(CustomDataset):
             - If is string, it should be a file path, and the every line of
               the file is a name of a class.
             - If is a sequence of string, every item is a name of class.
-            - If is None, use ``cls.CLASSES`` or the names of sub folders
+            - If is None, the object won't have category information.
-              (If use the second way to arrange samples).
+              (Not recommended)
 
             Defaults to None.
         ann_file (str, optional): The annotation file. If is string, read

mmcls/datasets/pipelines/auto_augment.py

@@ -133,8 +133,8 @@ class RandAugment(object):
         When magnitude_std=0, we calculate the magnitude as follows:
 
         .. math::
-            \text{magnitude} = \frac{\text{magnitude\_level}}
+            \text{magnitude} = \frac{\text{magnitude_level}}
-            {\text{total\_level}} \times (\text{val2} - \text{val1})
+            {\text{totallevel}} \times (\text{val2} - \text{val1})
             + \text{val1}
     """
 

mmcls/datasets/pipelines/transforms.py

@@ -798,8 +798,8 @@ class CenterCrop(object):
           to perform the center crop with the ``crop_size_`` as:
 
         .. math::
-            \text{crop\_size\_} = \frac{\text{crop\_size}}{\text{crop\_size} +
+            \text{crop_size_} = \frac{\text{crop_size}}{\text{crop_size} +
-            \text{crop\_padding}} \times \text{short\_edge}
+            \text{crop_padding}} \times \text{short_edge}
 
         And then the pipeline resizes the img to the input crop size.
     """

mmcls/models/backbones/tnt.py

@@ -201,8 +201,9 @@ class PixelEmbed(BaseModule):
 
 @BACKBONES.register_module()
 class TNT(BaseBackbone):
-    """ Transformer in Transformer
+    """Transformer in Transformer.
-    A PyTorch implement of : `Transformer in Transformer
+
+    A PyTorch implement of: `Transformer in Transformer
     <https://arxiv.org/abs/2103.00112>`_
 
     Inspiration from

mmcls/models/heads/deit_head.py

@@ -9,6 +9,24 @@ from .vision_transformer_head import VisionTransformerClsHead
 
 @HEADS.register_module()
 class DeiTClsHead(VisionTransformerClsHead):
+    """Distilled Vision Transformer classifier head.
+
+    Comparing with the :class:`VisionTransformerClsHead`, this head adds an
+    extra linear layer to handle the dist token. The final classification score
+    is the average of both linear transformation results of ``cls_token`` and
+    ``dist_token``.
+
+    Args:
+        num_classes (int): Number of categories excluding the background
+            category.
+        in_channels (int): Number of channels in the input feature map.
+        hidden_dim (int): Number of the dimensions for hidden layer.
+            Defaults to None, which means no extra hidden layer.
+        act_cfg (dict): The activation config. Only available during
+            pre-training. Defaults to ``dict(type='Tanh')``.
+        init_cfg (dict): The extra initialization configs. Defaults to
+            ``dict(type='Constant', layer='Linear', val=0)``.
+    """
 
     def __init__(self, *args, **kwargs):
         super(DeiTClsHead, self).__init__(*args, **kwargs)

mmcls/models/heads/vision_transformer_head.py

@@ -20,10 +20,12 @@ class VisionTransformerClsHead(ClsHead):
         num_classes (int): Number of categories excluding the background
             category.
         in_channels (int): Number of channels in the input feature map.
-        hidden_dim (int): Number of the dimensions for hidden layer. Only
+        hidden_dim (int): Number of the dimensions for hidden layer.
-            available during pre-training. Default None.
+            Defaults to None, which means no extra hidden layer.
         act_cfg (dict): The activation config. Only available during
-            pre-training. Defaults to Tanh.
+            pre-training. Defaults to ``dict(type='Tanh')``.
+        init_cfg (dict): The extra initialization configs. Defaults to
+            ``dict(type='Constant', layer='Linear', val=0)``.
     """
 
     def __init__(self,

mmcls/models/utils/augment/cutmix.py

@@ -117,7 +117,42 @@ class BaseCutMixLayer(object, metaclass=ABCMeta):
 
 @AUGMENT.register_module(name='BatchCutMix')
 class BatchCutMixLayer(BaseCutMixLayer):
-    """CutMix layer for batch CutMix."""
+    r"""CutMix layer for a batch of data.
+
+    CutMix is a method to improve the network's generalization capability. It's
+    proposed in `CutMix: Regularization Strategy to Train Strong Classifiers
+    with Localizable Features <https://arxiv.org/abs/1905.04899>`
+
+    With this method, patches are cut and pasted among training images where
+    the ground truth labels are also mixed proportionally to the area of the
+    patches.
+
+    Args:
+        alpha (float): Parameters for Beta distribution to generate the
+            mixing ratio. It should be a positive number. More details
+            can be found in :class:`BatchMixupLayer`.
+        num_classes (int): The number of classes
+        prob (float): The probability to execute cutmix. It should be in
+            range [0, 1]. Defaults to 1.0.
+        cutmix_minmax (List[float], optional): The min/max area ratio of the
+            patches. If not None, the bounding-box of patches is uniform
+            sampled within this ratio range, and the ``alpha`` will be ignored.
+            Otherwise, the bounding-box is generated according to the
+            ``alpha``. Defaults to None.
+        correct_lam (bool): Whether to apply lambda correction when cutmix bbox
+            clipped by image borders. Defaults to True.
+
+    Note:
+        If the ``cutmix_minmax`` is None, how to generate the bounding-box of
+        patches according to the ``alpha``?
+
+        First, generate a :math:`\lambda`, details can be found in
+        :class:`BatchMixupLayer`. And then, the area ratio of the bounding-box
+        is calculated by:
+
+        .. math::
+            \text{ratio} = \sqrt{1-\lambda}
+    """
 
     def __init__(self, *args, **kwargs):
         super(BatchCutMixLayer, self).__init__(*args, **kwargs)

mmcls/models/utils/augment/mixup.py

@@ -12,7 +12,8 @@ class BaseMixupLayer(object, metaclass=ABCMeta):
     """Base class for MixupLayer.
 
     Args:
-        alpha (float): Parameters for Beta distribution.
+        alpha (float): Parameters for Beta distribution to generate the
+            mixing ratio. It should be a positive number.
         num_classes (int): The number of classes.
         prob (float): MixUp probability. It should be in range [0, 1].
             Default to 1.0
@@ -36,7 +37,29 @@ class BaseMixupLayer(object, metaclass=ABCMeta):
 
 @AUGMENT.register_module(name='BatchMixup')
 class BatchMixupLayer(BaseMixupLayer):
-    """Mixup layer for batch mixup."""
+    r"""Mixup layer for a batch of data.
+
+    Mixup is a method to reduces the memorization of corrupt labels and
+    increases the robustness to adversarial examples. It's
+    proposed in `mixup: Beyond Empirical Risk Minimization
+    <https://arxiv.org/abs/1710.09412>`
+
+    This method simply linearly mix pairs of data and their labels.
+
+    Args:
+        alpha (float): Parameters for Beta distribution to generate the
+            mixing ratio. It should be a positive number. More details
+            are in the note.
+        num_classes (int): The number of classes.
+        prob (float): The probability to execute mixup. It should be in
+            range [0, 1]. Default sto 1.0.
+
+    Note:
+        The :math:`\alpha` (``alpha``) determines a random distribution
+        :math:`Beta(\alpha, \alpha)`. For each batch of data, we sample
+        a mixing ratio (marked as :math:`\lambda`, ``lam``) from the random
+        distribution.
+    """
 
     def __init__(self, *args, **kwargs):
         super(BatchMixupLayer, self).__init__(*args, **kwargs)

mmcls/models/utils/augment/resizemix.py

@@ -10,27 +10,31 @@ from .utils import one_hot_encoding
 
 @AUGMENT.register_module(name='BatchResizeMix')
 class BatchResizeMixLayer(BatchCutMixLayer):
-    r"""ResizeMix Random Paste layer for batch ResizeMix.
+    r"""ResizeMix Random Paste layer for a batch of data.
 
     The ResizeMix will resize an image to a small patch and paste it on another
-    image. More details can be found in `ResizeMix: Mixing Data with Preserved
+    image. It's proposed in `ResizeMix: Mixing Data with Preserved Object
-    Object Information and True Labels <https://arxiv.org/abs/2012.11101>`_
+    Information and True Labels <https://arxiv.org/abs/2012.11101>`_
 
     Args:
-        alpha (float): Parameters for Beta distribution. Positive(>0)
+        alpha (float): Parameters for Beta distribution to generate the
+            mixing ratio. It should be a positive number. More details
+            can be found in :class:`BatchMixupLayer`.
         num_classes (int): The number of classes.
         lam_min(float): The minimum value of lam. Defaults to 0.1.
         lam_max(float): The maximum value of lam. Defaults to 0.8.
         interpolation (str): algorithm used for upsampling:
-         'nearest' | 'linear' | 'bilinear' | 'bicubic' | 'trilinear' | 'area'.
+            'nearest' | 'linear' | 'bilinear' | 'bicubic' | 'trilinear' |
-         Default to 'bilinear'.
+            'area'. Default to 'bilinear'.
-        prob (float): mix probability. It should be in range [0, 1].
+        prob (float): The probability to execute resizemix. It should be in
-            Default to 1.0.
+            range [0, 1]. Defaults to 1.0.
-        cutmix_minmax (List[float], optional): cutmix min/max image ratio.
+        cutmix_minmax (List[float], optional): The min/max area ratio of the
-            (as percent of image size). When cutmix_minmax is not None, we
+            patches. If not None, the bounding-box of patches is uniform
-            generate cutmix bounding-box using cutmix_minmax instead of alpha
+            sampled within this ratio range, and the ``alpha`` will be ignored.
+            Otherwise, the bounding-box is generated according to the
+            ``alpha``. Defaults to None.
         correct_lam (bool): Whether to apply lambda correction when cutmix bbox
-            clipped by image borders. Default to True
+            clipped by image borders. Defaults to True
         **kwargs: Any other parameters accpeted by :class:`BatchCutMixLayer`.
 
     Note:
@@ -45,7 +49,7 @@ class BatchResizeMixLayer(BatchCutMixLayer):
         And the resize ratio of source images is calculated by :math:`\lambda`:
 
         .. math::
-            \text{ratio} = \sqrt{1-lam}
+            \text{ratio} = \sqrt{1-\lambda}
     """
 
     def __init__(self,

mmcls/models/utils/helpers.py

@@ -8,6 +8,8 @@ from mmcv.utils import digit_version
 
 
 def is_tracing() -> bool:
+    """Determine whether the model is called during the tracing of code with
+    ``torch.jit.trace``."""
     if digit_version(torch.__version__) >= digit_version('1.6.0'):
         on_trace = torch.jit.is_tracing()
         # In PyTorch 1.6, torch.jit.is_tracing has a bug.
@@ -26,6 +28,15 @@ def is_tracing() -> bool:
 
 # From PyTorch internals
 def _ntuple(n):
+    """A `to_tuple` function generator.
+
+    It returns a function, this function will repeat the input to a tuple of
+    length ``n`` if the input is not an Iterable object, otherwise, return the
+    input directly.
+
+    Args:
+        n (int): The number of the target length.
+    """
 
     def parse(x):
         if isinstance(x, collections.abc.Iterable):

mmcls/utils/logger.py

@@ -7,6 +7,16 @@ from mmcv.utils import get_logger
 
 
 def get_root_logger(log_file=None, log_level=logging.INFO):
+    """Get root logger.
+
+    Args:
+        log_file (str, optional): File path of log. Defaults to None.
+        log_level (int, optional): The level of logger.
+            Defaults to :obj:`logging.INFO`.
+
+    Returns:
+        :obj:`logging.Logger`: The obtained logger
+    """
     return get_logger('mmcls', log_file, log_level)