analysis.md

# Analysis

<!-- TOC -->

- [Log Analysis](#log-analysis)
  - [Plot Curves](#plot-curves)
  - [Calculate Training Time](#calculate-training-time)
- [Result Analysis](#result-analysis)
  - [Evaluate Results](#evaluate-results)
  - [View Typical Results](#view-typical-results)
- [Model Complexity](#model-complexity)
- [FAQs](#faqs)

<!-- TOC -->

## Log Analysis

### Plot Curves

`tools/analysis_tools/analyze_logs.py` plots curves of given keys according to the log files.

<div align=center><img src="../_static/image/tools/analysis/analyze_log.jpg" style=" width: 75%; height: 30%; "></div>

```shell
python tools/analysis_tools/analyze_logs.py plot_curve  \
    ${JSON_LOGS}  \
    [--keys ${KEYS}]  \
    [--title ${TITLE}]  \
    [--legend ${LEGEND}]  \
    [--backend ${BACKEND}]  \
    [--style ${STYLE}]  \
    [--out ${OUT_FILE}]  \
    [--window-size ${WINDOW_SIZE}]
```

**Description of all arguments**：

- `json_logs` : The paths of the log files, separate multiple files by spaces.
- `--keys` : The fields of the logs to analyze, separate multiple keys by spaces. Defaults to 'loss'.
- `--title` : The title of the figure. Defaults to use the filename.
- `--legend` : The names of legend, the number of which must be equal to `len(${JSON_LOGS}) * len(${KEYS})`. Defaults to use `"${JSON_LOG}-${KEYS}"`.
- `--backend` : The backend of matplotlib. Defaults to auto selected by matplotlib.
- `--style` : The style of the figure. Default to `whitegrid`.
- `--out` : The path of the output picture. If not set, the figure won't be saved.
- `--window-size`: The shape of the display window. The format should be `'W*H'`. Defaults to `'12*7'`.

```{note}
The `--style` option depends on `seaborn` package, please install it before setting it.
```

Examples:

- Plot the loss curve in training.

  ```shell
  python tools/analysis_tools/analyze_logs.py plot_curve your_log_json --keys loss --legend loss
  ```

- Plot the top-1 accuracy and top-5 accuracy curves, and save the figure to results.jpg.

  ```shell
  python tools/analysis_tools/analyze_logs.py plot_curve your_log_json --keys accuracy_top-1 accuracy_top-5  --legend top1 top5 --out results.jpg
  ```

- Compare the top-1 accuracy of two log files in the same figure.

  ```shell
  python tools/analysis_tools/analyze_logs.py plot_curve log1.json log2.json --keys accuracy_top-1 --legend exp1 exp2
  ```

```{note}
The tool will automatically select to find keys in training logs or validation logs according to the keys.
Therefore, if you add a custom evaluation metric, please also add the key to `TEST_METRICS` in this tool.
```

### Calculate Training Time

`tools/analysis_tools/analyze_logs.py` can also calculate the training time according to the log files.

```shell
python tools/analysis_tools/analyze_logs.py cal_train_time \
    ${JSON_LOGS}
    [--include-outliers]
```

**Description of all arguments**:

- `json_logs` : The paths of the log files, separate multiple files by spaces.
- `--include-outliers` : If set, include the first iteration in each epoch (Sometimes the time of first iterations is longer).

Example:

```shell
python tools/analysis_tools/analyze_logs.py cal_train_time work_dirs/some_exp/20200422_153324.log.json
```

The output is expected to be like the below.

```text
-----Analyze train time of work_dirs/some_exp/20200422_153324.log.json-----
slowest epoch 68, average time is 0.3818
fastest epoch 1, average time is 0.3694
time std over epochs is 0.0020
average iter time: 0.3777 s/iter
```

## Result Analysis

With the `--out` argument in `tools/test.py`, we can save the inference results of all samples as a file.
And with this result file, we can do further analysis.

### Evaluate Results

`tools/analysis_tools/eval_metric.py` can evaluate metrics again.

```shell
python tools/analysis_tools/eval_metric.py \
      ${CONFIG} \
      ${RESULT} \
      [--metrics ${METRICS}]  \
      [--cfg-options ${CFG_OPTIONS}] \
      [--metric-options ${METRIC_OPTIONS}]
```

Description of all arguments:

- `config` : The path of the model config file.
- `result`:  The Output result file in json/pickle format from `tools/test.py`.
- `--metrics` : Evaluation metrics, the acceptable values depend on the dataset.
- `--cfg-options`: If specified, the key-value pair config will be merged into the config file, for more details please refer to [Tutorial 1: Learn about Configs](../tutorials/config.md)
- `--metric-options`: If specified, the key-value pair arguments will be passed to the `metric_options` argument of dataset's `evaluate` function.

```{note}
In `tools/test.py`, we support using `--out-items` option to select which kind of results will be saved. Please ensure the result file includes "class_scores" to use this tool.
```

**Examples**:

```shell
python tools/analysis_tools/eval_metric.py configs/t2t_vit/t2t-vit-t-14_8xb64_in1k.py your_result.pkl --metrics accuracy --metric-options "topk=(1,5)"
```

### View Typical Results

`tools/analysis_tools/analyze_results.py` can save the images with the highest scores in successful or failed prediction.

```shell
python tools/analysis_tools/analyze_results.py \
      ${CONFIG} \
      ${RESULT} \
      [--out-dir ${OUT_DIR}] \
      [--topk ${TOPK}] \
      [--cfg-options ${CFG_OPTIONS}]
```

**Description of all arguments**:

- `config` : The path of the model config file.
- `result`:  Output result file in json/pickle format from `tools/test.py`.
- `--out-dir`: Directory to store output files.
- `--topk`: The number of images in successful or failed prediction with the highest `topk` scores to save. If not specified, it will be set to 20.
- `--cfg-options`: If specified, the key-value pair config will be merged into the config file, for more details please refer to [Tutorial 1: Learn about Configs](../tutorials/config.md)

```{note}
In `tools/test.py`, we support using `--out-items` option to select which kind of results will be saved. Please ensure the result file includes "pred_score", "pred_label" and "pred_class" to use this tool.
```

**Examples**:

```shell
python tools/analysis_tools/analyze_results.py \
       configs/resnet/resnet50_b32x8_imagenet.py \
       result.pkl \
       --out-dir results \
       --topk 50
```

## Model Complexity

### Get the FLOPs and params (experimental)

We provide a script adapted from [flops-counter.pytorch](https://github.com/sovrasov/flops-counter.pytorch) to compute the FLOPs and params of a given model.

```shell
python tools/analysis_tools/get_flops.py ${CONFIG_FILE} [--shape ${INPUT_SHAPE}]
```

Description of all arguments:

- `config` : The path of the model config file.
- `--shape`: Input size, support single value or double value parameter, such as `--shape 256` or `--shape 224 256`. If not set, default to be `224 224`.

You will get a result like this.

```text
==============================
Input shape: (3, 224, 224)
Flops: 4.12 GFLOPs
Params: 25.56 M
==============================
```

```{warning}
This tool is still experimental and we do not guarantee that the number is correct. You may well use the result for simple comparisons, but double-check it before you adopt it in technical reports or papers.
- FLOPs are related to the input shape while parameters are not. The default input shape is (1, 3, 224, 224).
- Some operators are not counted into FLOPs like GN and custom operators. Refer to [`mmcv.cnn.get_model_complexity_info()`](https://github.com/open-mmlab/mmcv/blob/master/mmcv/cnn/utils/flops_counter.py) for details.
```

## FAQs

- None