The "fitness" function in train.py.

[snop222]

In the train.py, line 29, as folowing:

from utils.general import labels_to_class_weights, increment_path, labels_to_image_weights, init_seeds, \
fitness, strip_optimizer, get_latest_run, check_dataset, check_file, check_git_status, check_img_size, \
check_requirements, print_mutation, set_logging, one_cycle, colorstr

The "fitness" actually is a function defined in "utils/metrics.py".
Why it is imported "from" by "utils.general" ?
But, the train.py could be running with no error report ?

[github-actions]

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[glenn-jocher]

@snop222 fitness() defines a model fitness based on a weighted combination of metrics. We use fitness for hyperparameter evolution and to decide when to save a new best.pt checkpoint.

yolov5/utils/metrics.py

Lines 12 to 16 in efa4946

	def fitness(x):
	# Model fitness as a weighted combination of metrics
	w = [0.0, 0.0, 0.1, 0.9] # weights for [P, R, mAP@0.5, mAP@0.5:0.95]
	return (x[:, :4] * w).sum(1)

The function itself is in metrics.py as you noted. In train.py it could be imported directly from metrics.py, it is imported from general.py since it is already available there due to a previous import:

yolov5/utils/general.py

Line 21 in efa4946

from utils.metrics import fitness

[snop222]

Thank you vrey much.

[github-actions]

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