Removed some numpy warnings [skip hazardlib][demos]
Removed some numpy warnings [skip hazardlib][demos]


Former-commit-id: 6a3bf4533e41b53ccd865885905fc725a079909f [formerly 6a3bf4533e41b53ccd865885905fc725a079909f [formerly f6c27064665c85981adbda87e593e6ba20f55c6c]]
Former-commit-id: dd885ad5e5d7f3aac27ef7960497d5fc70f69bce
Former-commit-id: d37fb2c3c0c8a67802c9d3a7cc23ce5ffb7fada0
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine