33. Huber loss
huber_loss()Asked in screens shaped like: NVIDIA, Jane Street
Mean Huber loss of labels y and predictions yhat with delta = 1. For each residual r = yhat - y: 0.5 r^2 if |r| <= 1, else |r| - 0.5. Round to 4 decimals.
Examples
Example 1
Input: { "y": [0, 0, 0], "yhat": [0.5, 2, 0] } Output: 0.5417
Constraints
- 1 <= n <= 10**5, where n is the length of the input
- Input is non-empty
Implement huber_loss(). Types below are the NumPy contract; Python and PyTorch use lists or tensors with the same names.
| Name | Type | I/O |
|---|---|---|
| y | array | Input |
| yhat | array | Input |
| value | float | Output |
Same tests, three APIs. Pick a language with the chips above the editor.
NumPy
Vectorized arrays. Default for analyst, scientist, and DE screens.
Revealed one at a time. The reference implementation stays in the Solution tab.
Hint 1
Keep the function signature. Fill the body — do not rename parameters.
Hint 2
Match the rounding in the examples. Tests compare with a small numeric tolerance.
Hint 3
Switch NumPy / Python / PyTorch with the chips above the editor. Each language has its own tests.
Run your code to see stdout.
Submit to run the checks.
All tests passed on this language.
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