* Update val.py

Add an option to choose number of workers if not called by train.py

* Update comment

* 120 char line width

Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* Refactor new `model.warmup()` method

* Add half

* Fix float zeros format

* 255 to integer

* Update `set_logging()`

* Update export.py

* pre-commit fixes

* Update LoadImages

* Update LoadStreams

* Update print_args

* Single LOGGER definition

* yolo.py fix

Co-authored-by: pre-commit <pre-commit@example.com>

* use os.path.relpath instead of relative_to

* use os.path.relpath instead of relative_to

* Remove os.path from val.py

* Remove os.path from train.py

* Update detect.py import to os

* Update export.py import to os

Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* Update val.py `pad = 0.0 if task == speed else 0.5`

* Cleanup

* Allow YOLOv5 execution from arbitrary `cwd`

* Fix str bugs

* Validate best.pt on train end

* 0.7 iou for COCO only

* pass callbacks

* active model.float() if not half

* print Validating best.pt...

* add newline

* Simplify `check_requirements()` usage

* remove assert, print()

* Update `sys.path.append(str(ROOT))`

* Cleanup

* Refactor argparser printing to `print_args()`

* Cleanup

* Fix val.py study plot

* call plot_val_study

* Rename plot_study_txt to plot_val_study

* Improved detect.py timing

* Eliminate 1 time_sync() call

* Inference-only time

* dash

* #Save section

* Cleanup

* Add suffix checks

* Cleanup

* Cleanup2

* Cleanup3

* added callbacks

* added back callback to main

* added save_dir to callback output

* reduced code count

* updated callbacks

* added default callback class to main, added missing parameters to on_model_save

* Glenn updates

Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* Implement new headers

* Reformat 1

* Reformat 2

* Reformat 3 - math

* Reformat 4 - yaml

* Update AP calculation

* Cleanup

* Remove original

* added callbacks

* Update callbacks.py

* Update train.py

* Update val.py

* Fix CamlCase add staticmethod

* Refactor logger into callbacks

* Cleanup

* New callback on_val_image_end()

* Add curves and results images to TensorBoard

Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* PyCharm reformat

* YAML reformat

* Markdown reformat

* Train from `--data path/to/dataset.zip` feature

* Update dataset_stats()

* cleanup

* cleanup2

* Update download script headers

* cleanup

* bug fix attempt

* bug fix attempt2

* bug fix attempt3

* cleanup

* New CSV Logger

* cleanup

* move batch plots into Logger

* rename comment

* Remove total loss from progress bar

* mloss :-1 bug fix

* Update plot_results()

* Update plot_results()

* plot_results bug fix

* Update loggers

* Config

* Update val.py

* cleanup

* fix1

* fix2

* fix3 and reformat

* format sweep.py

* Logger() class

* cleanup

* cleanup2

* wandb package import fix

* wandb package import fix2

* txt fix

* fix4

* fix5

* fix6

* drop wandb into utils/loggers

* fix 7

* rename loggers/wandb_logging to loggers/wandb

* Update message

* Update message

* Update message

* cleanup

* Fix x axis bug

* fix rank 0 issue

* cleanup

* Add yolov5/ to path

* rename functions to run()

* cleanup

* rename fix

* CI fix

* cleanup find models/export.py

* Update DDP for `torch.distributed.run`

* Add LOCAL_RANK

* remove opt.local_rank

* backend="gloo|nccl"

* print

* print

* debug

* debug

* os.getenv

* gloo

* gloo

* gloo

* cleanup

* fix getenv

* cleanup

* cleanup destroy

* try nccl

* return opt

* add --local_rank

* add timeout

* add init_method

* gloo

* move destroy

* move destroy

* move print(opt) under if RANK

* destroy only RANK 0

* move destroy inside train()

* restore destroy outside train()

* update print(opt)

* cleanup

* nccl

* gloo with 60 second timeout

* update namespace printing

* Slightly modify CLI execution

This simple change makes it easier to run the primary functions of this
repo (train/detect/test) from within Python. An object which represents
`opt` can be constructed and fed to the `main` function of each of these
modules, rather than having to call the lower level functions directly,
or run the module as a script.

* Update export.py

Add CLI parsing update for more convenient module usage within Python.

Co-authored-by: Lewis Belcher <lb@desupervised.io>

* Refactoring cleanup

* Update test.py

* remove opt from test()

* pass kwargs

* update comments

* revert accidental default change

* multiple --img options

* add comments