From 4f5d93ecd0c5ba5de0ead54d8934f163550d27d2 Mon Sep 17 00:00:00 2001
From: Nicolas Patry <patry.nicolas@protonmail.com>
Date: Fri, 1 Sep 2023 00:22:03 +0200
Subject: [PATCH] Fixing top_k tokens when k ends up < 0 (#966)

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Fixes # (issue)


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---
 server/text_generation_server/utils/tokens.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/server/text_generation_server/utils/tokens.py b/server/text_generation_server/utils/tokens.py
index 69177d56..7b003f1d 100644
--- a/server/text_generation_server/utils/tokens.py
+++ b/server/text_generation_server/utils/tokens.py
@@ -363,9 +363,10 @@ def batch_top_tokens(
     # Find the new "fuzzy" top n values
     top_n_indices = (logprobs >= nth_highest).nonzero()
     _, top_n_ishes = torch.unique_consecutive(top_n_indices[:, 0], return_counts=True)
-
+ 
+    k = 1 if top_n_ishes.numel() == 0 else top_n_ishes.max()
     # Take a new topk for these new max n values
-    top_k = torch.topk(logprobs, k=top_n_ishes.max(), dim=1, sorted=True)
+    top_k = torch.topk(logprobs, k=k, dim=1, sorted=True)
 
     top_n_ishes = top_n_ishes.tolist()
     top_indices = top_k.indices.tolist()