Fix CircularBuffer backfill broadcast for >2D data#1046
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The first-push backfill in CircularBuffer.append hard-coded a 3-D broadcast (is_first_push[None, :, None] and data[None, :, :]), which only lines up when the buffer is exactly (max_len, batch, feature). DcMotorActuator with a variable delay lag range stacks position, velocity, and effort targets into a 3-D tensor (num_envs, num_targets, 3), making the buffer 4-D. The hard-coded condition then misaligns the batch axis with the num_targets axis and raises a broadcast error whenever num_envs != num_targets. The fix derives the broadcast shape from data.ndim so it works for tensors of any rank. Supersedes #1045. Co-authored-by: ZzzzzzS <ZhouZishun@mail.zzshub.cn>
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rdeits-bd
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Ah sorry about that and thanks for the fix. I don't see any new CUDA sync issues after this change.
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The first-push backfill in CircularBuffer.append hard-coded a 3-D broadcast (is_first_push[None, :, None] and data[None, :, :]), which only lines up when the buffer is exactly (max_len, batch, feature). DcMotorActuator with a variable delay lag range stacks position, velocity, and effort targets into a 3-D tensor (num_envs, num_targets, 3), making the buffer 4-D. The hard-coded condition then misaligns the batch axis with the num_targets axis and raises a broadcast error whenever num_envs != num_targets. The fix derives the broadcast shape from data.ndim so it works for tensors of any rank. Supersedes mujocolab#1045. Co-authored-by: ZzzzzzS <ZhouZishun@mail.zzshub.cn>
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CircularBuffer.appendcrashed with a broadcast mismatch when the buffered data had more than two dimensions. The first-push backfill hard-coded a 3-D broadcast, which misaligns the batch axis with the trailing axis onceDcMotorActuator's variable delay stacks targets into a 3-D tensor. It now derives the broadcast shape fromdata.ndimso backfill works for any rank. The regression came from #1031, which swapped the dimension-agnostic mask for a sync-freetorch.wherebut baked in 3-D views.Supersedes #1045 by @ZzzzzzS, who diagnosed the bug and wrote an equivalent fix (credited as co-author).