{"record":{"id":"0631c066efda244b","repo":"keras-team/keras","slug":"argument-output-must-be-at-least-rank-1-receive-0631c0","errorCode":null,"errorMessage":"Argument `output` must be at least rank 1. Received: output.shape={output.shape}","messagePattern":"Argument `output` must be at least rank 1\\. Received: output\\.shape=(.+?)","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"keras/src/backend/jax/ops/nn.py","lineNumber":999,"sourceCode":"        )\n\n    if from_logits:\n        log_prob = jax.nn.log_softmax(output, axis=axis)\n    else:\n        output = output / jnp.sum(output, axis, keepdims=True)\n        output = jnp.clip(output, backend.epsilon(), 1.0 - backend.epsilon())\n        log_prob = jnp.log(output)\n    return -jnp.sum(target * log_prob, axis=axis)\n\n\ndef sparse_categorical_crossentropy(target, output, from_logits=False, axis=-1):\n    target = jnp.array(target, dtype=\"int32\")\n    output = jnp.array(output)\n    if len(target.shape) == len(output.shape) and target.shape[-1] == 1:\n        target = jnp.squeeze(target, axis=-1)\n\n    if len(output.shape) < 1:\n        raise ValueError(\n            \"Argument `output` must be at least rank 1. \"\n            \"Received: \"\n            f\"output.shape={output.shape}\"\n        )\n    if target.shape != output.shape[:-1]:\n        raise ValueError(\n            \"Arguments `target` and `output` must have the same shape \"\n            \"up until the last dimension: \"\n            f\"target.shape={target.shape}, output.shape={output.shape}\"\n        )\n    if from_logits:\n        log_prob = jax.nn.log_softmax(output, axis=axis)\n    else:\n        output = output / jnp.sum(output, axis, keepdims=True)\n        output = jnp.clip(output, backend.epsilon(), 1.0 - backend.epsilon())\n        log_prob = jnp.log(output)\n    target = jnn.one_hot(target, output.shape[axis], axis=axis)\n    return -jnp.sum(target * log_prob, axis=axis)","sourceCodeStart":981,"sourceCodeEnd":1017,"githubUrl":"https://github.com/keras-team/keras/blob/7a34a03db60bf60042242d6a556fc3be119046a5/keras/src/backend/jax/ops/nn.py#L981-L1017","documentation":"Error \"Argument `output` must be at least rank 1. Received: output.shape={output.shape}\" thrown in keras-team/keras.","triggerScenarios":"Thrown at keras/src/backend/jax/ops/nn.py:999 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"7a34a03db60bf60042242d6a556fc3be119046a5","analyzedAt":"2026-08-25T21:25:25.994Z","schemaVersion":2},"datasetVersion":"2026-08-26T02:17:13.382Z"}