huggingface/pytorch-image-models · error · ValueError

schedule_random_mix must be between 0 and 1.

Error message

schedule_random_mix must be between 0 and 1.

What it means

schedule_random_mix — the fraction of batches randomly mixed between choice levels in a progressive schedule — must lie in [0, 1]; values outside that range are rejected at construction.

Source

Thrown at timm/data/scheduled_sampler.py:80

        if len(sampler) <= 0:
            raise ValueError('ScheduledBatchSampler requires a non-empty sampler.')
        if not batch_sizes:
            raise ValueError('batch_sizes must contain at least one value.')
        if any(int(batch_size) != batch_size or batch_size <= 0 for batch_size in batch_sizes):
            raise ValueError('All scheduled batch sizes must be positive integers.')
        if num_batches is not None and (int(num_batches) != num_batches or num_batches <= 0):
            raise ValueError('num_batches must be a positive integer when specified.')
        if choice_schedule not in ('constant', 'progressive'):
            raise ValueError("choice_schedule must be 'constant' or 'progressive'.")
        if choice_schedule == 'progressive':
            if len(batch_sizes) < 2:
                raise ValueError('A progressive schedule requires at least two choices.')
            if schedule_epochs is None or int(schedule_epochs) != schedule_epochs or schedule_epochs <= 0:
                raise ValueError('schedule_epochs must be a positive integer for a progressive schedule.')
            if schedule_spread < 0:
                raise ValueError('schedule_spread must be non-negative.')
            if not 0 <= schedule_random_mix <= 1:
                raise ValueError('schedule_random_mix must be between 0 and 1.')

        self.sampler = sampler
        self.batch_sizes = tuple(int(batch_size) for batch_size in batch_sizes)
        self.choice_weights = self._normalize_choice_weights(choice_weights)
        self._active_choices = tuple(
            choice_index
            for choice_index, choice_weight in enumerate(self.choice_weights)
            if choice_weight > 0
        )
        self.seed = seed
        self.drop_last = drop_last
        self.shuffle_schedule = shuffle_schedule
        self.choice_schedule = choice_schedule
        self.schedule_epochs = int(schedule_epochs) if schedule_epochs is not None else None
        self.schedule_spread = schedule_spread
        self.schedule_random_mix = schedule_random_mix
        self.epoch = 0
        self.average_batch_size = self._calculate_average_batch_size()

View on GitHub (pinned to 9a5261e31b)

Solutions

  1. Express the value as a fraction in [0,1] (e.g. 0.1 for 10% random mixing).
  2. If it's not needed, leave it at the default 0.1 or set 0.

Example fix

# before
schedule_random_mix=10  # meant 10%

# after
schedule_random_mix=0.1
Defensive patterns

Strategy: validation

Validate before calling

assert schedule_random_mix is None or 0 <= schedule_random_mix <= 1

Prevention

When it happens

Trigger: choice_schedule='progressive' with schedule_random_mix=1.5, -0.1, or 10.

Common situations: Config typo (extra digit); expressing the mix as a percentage (10 for 10%) instead of a fraction (0.1).

Related errors


AI-assisted analysis of huggingface/pytorch-image-models@9a5261e31b (2026-08-27). Data as JSON: /api/errors/f30e1fea9e0297cc. Report an issue: GitHub.