def test_temperature_dist_warper(self):
        input_ids = None
        length = 20

        scores = self._get_uniform_logits(batch_size=2, length=length)

        # tweak scores to not be uniform anymore
        scores[1, 5] = (1 / length) + 0.1  # peak, 1st batch
        scores[1, 10] = (1 / length) - 0.4  # valley, 1st batch

        # compute softmax
        probs = nn.functional.softmax(scores, dim=-1)

        temp_dist_warper_sharper = TemperatureLogitsWarper(temperature=0.5)
        temp_dist_warper_smoother = TemperatureLogitsWarper(temperature=1.3)

        warped_prob_sharp = nn.functional.softmax(temp_dist_warper_sharper(input_ids, scores.clone()), dim=-1)
        warped_prob_smooth = nn.functional.softmax(temp_dist_warper_smoother(input_ids, scores.clone()), dim=-1)

        # uniform distribution stays uniform
        self.assertTrue(torch.allclose(probs[0, :], warped_prob_sharp[0, :], atol=1e-3))
        self.assertTrue(torch.allclose(probs[0, :], warped_prob_smooth[0, :], atol=1e-3))

        # sharp peaks get higher, valleys get lower
        self.assertLess(probs[1, :].max(), warped_prob_sharp[1, :].max())
        self.assertGreater(probs[1, :].min(), warped_prob_sharp[1, :].min())

        # smooth peaks get lower, valleys get higher
        self.assertGreater(probs[1, :].max(), warped_prob_smooth[1, :].max())
        self.assertLess(probs[1, :].min(), warped_prob_smooth[1, :].min())
 def _get_warper_and_kwargs(num_beams):
     warp_kwargs = {"top_k": 10, "top_p": 0.7, "temperature": 0.7}
     logits_warper = LogitsProcessorList(
         [
             TopKLogitsWarper(top_k=warp_kwargs["top_k"], min_tokens_to_keep=(2 if num_beams > 1 else 1)),
             TopPLogitsWarper(top_p=warp_kwargs["top_p"], min_tokens_to_keep=(2 if num_beams > 1 else 1)),
             TemperatureLogitsWarper(warp_kwargs["temperature"]),
         ]
     )
     return warp_kwargs, logits_warper
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    def test_processor_list(self):
        batch_size = 4
        sequence_length = 10
        vocab_size = 15
        eos_token_id = 0

        # dummy input_ids and scores
        input_ids = ids_tensor((batch_size, sequence_length), vocab_size)
        input_ids_comp = input_ids.clone()

        scores = self._get_uniform_logits(batch_size, vocab_size)
        scores_comp = scores.clone()

        # instantiate all dist processors
        min_dist_proc = MinLengthLogitsProcessor(min_length=10,
                                                 eos_token_id=eos_token_id)
        temp_dist_warp = TemperatureLogitsWarper(temperature=0.5)
        rep_penalty_proc = RepetitionPenaltyLogitsProcessor(penalty=2.0)
        top_k_warp = TopKLogitsWarper(3)
        top_p_warp = TopPLogitsWarper(0.8)
        no_repeat_proc = NoRepeatNGramLogitsProcessor(2)
        no_bad_words_dist_proc = NoBadWordsLogitsProcessor(
            bad_words_ids=[[1]], eos_token_id=eos_token_id)

        # no processor list
        scores = min_dist_proc(input_ids, scores)
        scores = temp_dist_warp(input_ids, scores)
        scores = rep_penalty_proc(input_ids, scores)
        scores = top_k_warp(input_ids, scores)
        scores = top_p_warp(input_ids, scores)
        scores = no_repeat_proc(input_ids, scores)
        scores = no_bad_words_dist_proc(input_ids, scores)

        # with processor list
        processor = LogitsProcessorList([
            min_dist_proc,
            temp_dist_warp,
            rep_penalty_proc,
            top_k_warp,
            top_p_warp,
            no_repeat_proc,
            no_bad_words_dist_proc,
        ])
        scores_comp = processor(input_ids, scores_comp)

        # scores should be equal
        self.assertTrue(torch.allclose(scores, scores_comp, atol=1e-3))

        # input_ids should never be changed
        self.assertListEqual(input_ids.tolist(), input_ids_comp.tolist())
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    def _get_logits_warper_list(num_beams, temperature, top_k, top_p):
        warpers = LogitsProcessorList()
        if temperature is not None and temperature != 1.0:
            warpers.append(TemperatureLogitsWarper(temperature))

        if top_k is not None and top_k != 0:
            warpers.append(
                TopKLogitsWarper(
                    top_k=top_k,
                    min_tokens_to_keep=(2 if num_beams > 1 else 1)))

        if top_p is not None and top_p < 1.0:
            warpers.append(
                TopPLogitsWarper(
                    top_p=top_p,
                    min_tokens_to_keep=(2 if num_beams > 1 else 1)))
        return warpers