Merge node error for multi_context evolutions #647
Description
Describe the bug
Runner in Executor raised an exception
Traceback (most recent call last):
File "/home/user/anaconda3/envs/ragas/lib/python3.10/site-packages/ragas/executor.py", line 58, in _aresults
r = await future
File "/home/user/anaconda3/envs/ragas/lib/python3.10/asyncio/tasks.py", line 575, in _wait_for_one
return f.result() # May raise f.exception().
File "/home/user/anaconda3/envs/ragas/lib/python3.10/site-packages/ragas/executor.py", line 91, in wrapped_callable_async
return counter, await callable(*args, **kwargs)
File "/home/user/anaconda3/envs/ragas/lib/python3.10/site-packages/ragas/testset/evolutions.py", line 163, in evolve
return await self.generate_datarow(
File "/home/user/anaconda3/envs/ragas/lib/python3.10/site-packages/ragas/testset/evolutions.py", line 210, in generate_datarow
merged_nodes = self.merge_nodes(relevant_context)
File "/home/user/anaconda3/envs/ragas/lib/python3.10/site-packages/ragas/testset/evolutions.py", line 75, in merge_nodes
embed_dim = len(nodes.nodes[0].embedding) if nodes.nodes[0].embedding else None
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()
Ragas version: 0.1.1
Python version: 3.10.0
This only happens for multi_context evolutions.