code: def _validate_vector(u, dtype=None):
      u = ivy.asarray(u, dtype=dtype)
      if u.ndim == 1:
          return u
      raise ValueError("Input vector should be 1-D.")
  
imports: import ivy
  from ivy.functional.frontends.numpy.func_wrapper import to_ivy_arrays_and_back
  import ivy.functional.frontends.scipy
label_desc: Use image node_id 1 for calling a global function with example usage: _validate_vector(u, dtype) and returns: u