From 4cce32f090d02ef84ad40fef6ef9bba7b9d65c9c Mon Sep 17 00:00:00 2001
From: Matthew Honnibal <honnibal+gh@gmail.com>
Date: Tue, 1 Sep 2020 16:38:34 +0200
Subject: [PATCH] Fix tagger initialization

---
 spacy/pipeline/tagger.pyx | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/spacy/pipeline/tagger.pyx b/spacy/pipeline/tagger.pyx
index c94cb6b58..f831caefe 100644
--- a/spacy/pipeline/tagger.pyx
+++ b/spacy/pipeline/tagger.pyx
@@ -289,7 +289,14 @@ class Tagger(Pipe):
             err = Errors.E1006.format(name="Tagger")
             raise ValueError(err)
         self.set_output(len(self.labels))
-        self.model.initialize(X=doc_sample)
+        if doc_sample:
+            label_sample = [
+                self.model.ops.alloc2f(len(doc), len(self.labels))
+                for doc in doc_sample
+            ]
+            self.model.initialize(X=doc_sample, Y=label_sample)
+        else:
+            self.model.initialize()
         if sgd is None:
             sgd = self.create_optimizer()
         return sgd