{"record":{"id":"ea07a50d4fc9fd4b","repo":"huggingface/pytorch-image-models","slug":"invalid-epsilon-value-ea07a5","errorCode":null,"errorMessage":"Invalid epsilon value: {}","messagePattern":"Invalid epsilon value: (.+?)","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"timm/optim/mars.py","lineNumber":115,"sourceCode":"    \"\"\"\n    def __init__(\n            self,\n            params: ParamsT,\n            lr: float = 3e-3,\n            betas: Tuple[float, float] = (0.9, 0.99),\n            eps: float = 1e-8,\n            weight_decay: float = 0.,\n            gamma: float = 0.025,\n            mars_type: str = \"adamw\",\n            optimize_1d: bool = False,\n            lr_1d_factor: float = 1.0,\n            betas_1d: Optional[Tuple[float, float]] = None,\n            caution: bool = False\n    ):\n        if not 0.0 <= lr:\n            raise ValueError(\"Invalid learning rate: {}\".format(lr))\n        if not 0.0 <= eps:\n            raise ValueError(\"Invalid epsilon value: {}\".format(eps))\n        if not 0.0 <= betas[0] < 1.0:\n            raise ValueError(\"Invalid beta parameter at index 0: {}\".format(betas[0]))\n        if not 0.0 <= betas[1] < 1.0:\n            raise ValueError(\"Invalid beta parameter at index 1: {}\".format(betas[1]))\n        assert mars_type in [\"adamw\", \"lion\"], \"MARS type not supported\"\n\n        defaults = dict(\n            lr=lr,\n            betas=betas,\n            eps=eps,\n            weight_decay=weight_decay,\n            mars_type=mars_type,\n            gamma=gamma,\n            optimize_1d=optimize_1d,\n            lr_1d_factor=lr_1d_factor,\n            betas_1d=betas_1d or betas,\n            caution=caution,\n        )","sourceCodeStart":97,"sourceCodeEnd":133,"githubUrl":"https://github.com/huggingface/pytorch-image-models/blob/9a5261e31b3b5128526eb2658333b4c0a54464ae/timm/optim/mars.py#L97-L133","documentation":"Mars validates that the epsilon hyperparameter is non-negative; a negative eps breaks the denominator in the Adam-style update and is rejected at construction.","triggerScenarios":"Constructing Mars(params, eps=-1e-8) or otherwise passing a negative epsilon.","commonSituations":"Sign typos; eps derived from arithmetic that can go negative in sweeps.","solutions":["Use a positive eps (default 1e-8 style values)","Correct the source of the negative eps"],"exampleFix":"# before\nopt = Mars(model.parameters(), eps=-1e-8)\n# after\nopt = Mars(model.parameters(), eps=1e-8)","handlingStrategy":"validation","validationCode":"assert cfg.eps >= 0, 'eps must be non-negative'","typeGuard":"def is_valid_eps(e: float) -> bool:\n    return isinstance(e, (int, float)) and e >= 0","tryCatchPattern":null,"preventionTips":["Default eps suffices in most cases","Sanitize config floats"],"tags":["optimizer","mars","epsilon","hyperparameter-validation"],"backgroundTag":"hyperparameter-out-of-range","analyzedSha":"9a5261e31b3b5128526eb2658333b4c0a54464ae","analyzedAt":"2026-08-27T02:34:25.417Z","schemaVersion":2},"datasetVersion":"2026-08-27T03:17:27.898Z"}