Hi
As far as I can remember you cannot use negative value for std and you should not be able to use as it does not make any sense mathematically.
To just verify, I ran it and it gives a proper error:
torch.manual_seed(8)
torch.normal(0, -1, (10, ))

# output
# RuntimeError                              Traceback (most recent call last)
# <ipython-input-6-f3bb1e6c1119> in <module>()
    #   1 torch.manual_seed(8)
# ----> 2 torch.normal(0, -1, (10, ))

# RuntimeError: normal_ expects std > 0.0, but found std=-1

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