fix bug with encoder relative pos emb

Author: lucidrains

setup.py

@@ -3,7 +3,7 @@
 setup(
   name = 'x-transformers',
   packages = find_packages(exclude=['examples']),
-  version = '0.0.19',
+  version = '0.0.20',
   license='MIT',
   description = 'X-Transformers - Pytorch',
   author = 'Phil Wang',

x_transformers/x_transformers.py

@@ -239,7 +239,7 @@ def __init__(self, dim, depth, dim_head = 64, heads = 8, use_scalenorm = False,
         super().__init__()
         self.dim = dim
         self.layers = nn.ModuleList([])
-        self.rel_pos = RelativePositionBias(causal = True) if rel_pos_bias else None
+        self.rel_pos = RelativePositionBias() if rel_pos_bias else None
 
         norm_class = ScaleNorm if use_scalenorm else nn.LayerNorm
         prenorm_fn = partial(PreNorm, dim, norm_class = norm_class)