diff --git a/pyproject.toml b/pyproject.toml
index 1726ef7..1732ca3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "FSRS-Optimizer"
-version = "5.0.9"
+version = "5.0.10"
 readme = "README.md"
 dependencies = [
     "matplotlib>=3.7.0",
diff --git a/src/fsrs_optimizer/fsrs_optimizer.py b/src/fsrs_optimizer/fsrs_optimizer.py
index 0a8b87f..78e31b5 100644
--- a/src/fsrs_optimizer/fsrs_optimizer.py
+++ b/src/fsrs_optimizer/fsrs_optimizer.py
@@ -213,7 +213,7 @@ def __init__(
         self.x_train = pad_sequence(
             dataframe["tensor"].to_list(), batch_first=True, padding_value=0
         )
-        self.t_train = torch.tensor(dataframe["delta_t"].values, dtype=torch.int)
+        self.t_train = torch.tensor(dataframe["delta_t"].values, dtype=torch.float)
         self.y_train = torch.tensor(dataframe["y"].values, dtype=torch.float)
         self.seq_len = torch.tensor(
             dataframe["tensor"].map(len).values, dtype=torch.long