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Mojo function

topk_topp_sampling_from_prob

def topk_topp_sampling_from_prob[dtype: DType, out_idx_type: DType, block_size: Int = Int(1024), from_logits: Bool = False, TopKArrLayoutType: TensorLayout = Layout[*?, *?], IndicesLayoutType: TensorLayout = Layout[*?, *?], TopPArrLayoutType: TensorLayout = Layout[*?, *?], SeedLayoutType: TensorLayout = Layout[*?, *?], TemperatureLayoutType: TensorLayout = Layout[*?, *?], MinPLayoutType: TensorLayout = Layout[*?, *?]](ctx: DeviceContext, probs: TileTensor[dtype, Storage=probs.Storage, address_space=probs.address_space, linear_idx_type=probs.linear_idx_type], output: TileTensor[out_idx_type, Storage=output.Storage, address_space=output.address_space, linear_idx_type=output.linear_idx_type], top_k_val: Int, top_p_val: Float32 = 1, deterministic: Bool = False, rng_seed: Optional[TileTensor[DType.uint64, SeedLayoutType, ImmutAnyOrigin]] = None, rng_offset: UInt64 = UInt64(0), indices: Optional[TileTensor[out_idx_type, IndicesLayoutType, ImmutAnyOrigin]] = None, top_k_arr: Optional[TileTensor[out_idx_type, TopKArrLayoutType, ImmutAnyOrigin]] = None, top_p_arr: Optional[TileTensor[DType.float32, TopPArrLayoutType, ImmutAnyOrigin]] = None, temperature: Optional[TileTensor[DType.float32, TemperatureLayoutType, ImmutAnyOrigin]] = None, min_p: Optional[TileTensor[DType.float32, MinPLayoutType, ImmutAnyOrigin]] = None)

Joint top-k + top-p sampling from probability distribution.

Performs stochastic sampling considering only tokens that satisfy both the top-k count constraint AND the top-p nucleus constraint. When top_p_val is 1.0 (default) this behaves identically to topk_sampling_from_prob.

When from_logits is True, probs contains raw logits: softmax with per-row temperature scaling and the optional min-p mask are fused into the sampling kernel, avoiding the [batch_size, d] probability round-trip through global memory and the separate softmax / mask kernel launches.

Parameters:

dtype (DType): Element type of the probs tensor.
out_idx_type (DType): Index type used for the sampled output indices.
block_size (Int): Number of threads per block (defaults to 1024).
from_logits (Bool): If True, probs holds raw logits and softmax with per-row temperature scaling and min-p masking is fused into the kernel (defaults to False).
TopKArrLayoutType (TensorLayout): Memory layout of the optional top_k_arr tensor.
IndicesLayoutType (TensorLayout): Memory layout of the optional indices tensor.
TopPArrLayoutType (TensorLayout): Memory layout of the optional top_p_arr tensor.
SeedLayoutType (TensorLayout): Memory layout of the optional rng_seed tensor.
TemperatureLayoutType (TensorLayout): Memory layout of the optional temperature tensor.
MinPLayoutType (TensorLayout): Memory layout of the optional min_p tensor.

Args:

ctx (DeviceContext): Device context for kernel execution.
probs (TileTensor[dtype, Storage=probs.Storage, address_space=probs.address_space, linear_idx_type=probs.linear_idx_type]): Input probability distribution [batch_size, d], or raw logits when from_logits is True.
output (TileTensor[out_idx_type, Storage=output.Storage, address_space=output.address_space, linear_idx_type=output.linear_idx_type]): Output sampled indices [batch_size].
top_k_val (Int): Default top-k value (number of top tokens to consider).
top_p_val (Float32): Default top-p value (nucleus probability threshold).
deterministic (Bool): Whether to use deterministic sampling.
rng_seed (Optional[TileTensor[DType.uint64, SeedLayoutType, ImmutAnyOrigin]]): Optional per-row seed tensor [batch_size], indexed by the request's logical row (see indices). If None, defaults to 0.
rng_offset (UInt64): Random offset for Random number generator.
indices (Optional[TileTensor[out_idx_type, IndicesLayoutType, ImmutAnyOrigin]]): Optional row indices for batch indexing [batch_size].
top_k_arr (Optional[TileTensor[out_idx_type, TopKArrLayoutType, ImmutAnyOrigin]]): Optional per-row top-k values [batch_size].
top_p_arr (Optional[TileTensor[DType.float32, TopPArrLayoutType, ImmutAnyOrigin]]): Optional per-row top-p values [batch_size].
temperature (Optional[TileTensor[DType.float32, TemperatureLayoutType, ImmutAnyOrigin]]): Optional per-row temperature values [batch_size]. Only used when from_logits is True; defaults to 1.0 per row.
min_p (Optional[TileTensor[DType.float32, MinPLayoutType, ImmutAnyOrigin]]): Optional per-row min-p thresholds [batch_size]. Only used when from_logits is True.

Raises:

Error: If tensor ranks or shapes are invalid.