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    ".. _less-than-zero:\n",
    "\n",
    "Less Than Zero Comparison\n",
    "=========================\n",
    "\n",
    "Here we demonstrate testing a secret-shared array elementwise to see if the values are less than zero.  The resulting secret shared array will be the same shape as the input, containing :math:`1` where the input is less than zero, and :math:`0` where it is not.  Note that we use the :any:`Boolean` encoding when we reveal the output because the default :any:`FixedPoint` encoding would produce unexpected results.\n",
    "\n",
    "Note that this comparison is roughly three times faster than using :ref:`less-than` with :math:`0` as the second operand.\n",
    "\n",
    "In this example, we will compare the vector :math:`[2, -1.5, 0]` to zero, which should return :math:`[0, 1, 0]`:"
   ]
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     "text": [
      "INFO:root:Player 0 secret: [ 2.  -1.5  0. ]\n",
      "INFO:root:Player 0 result: [False  True False]\n",
      "INFO:root:Player 1 result: [False  True False]\n",
      "INFO:root:Player 2 result: [False  True False]\n"
     ]
    }
   ],
   "source": [
    "import logging\n",
    "\n",
    "import numpy\n",
    "\n",
    "from cicada.additive import AdditiveProtocolSuite\n",
    "from cicada.communicator import SocketCommunicator\n",
    "from cicada.encoding import Boolean\n",
    "from cicada.logger import Logger\n",
    "\n",
    "logging.basicConfig(level=logging.INFO)\n",
    "\n",
    "def main(communicator):\n",
    "    log = Logger(logging.getLogger(), communicator)\n",
    "    protocol = AdditiveProtocolSuite(communicator)\n",
    "    \n",
    "    a = numpy.array([2, -1.5, 0]) if communicator.rank == 0 else None\n",
    "    \n",
    "    log.info(f\"Player {communicator.rank} secret: {a}\", src=0)\n",
    "\n",
    "    a_share = protocol.share(src=0, secret=a, shape=(3,))\n",
    "    less_zero_share = protocol.less_zero(a_share)\n",
    "    less_zero = protocol.reveal(less_zero_share, encoding=Boolean())\n",
    "    \n",
    "    log.info(f\"Player {communicator.rank} result: {less_zero}\")\n",
    "\n",
    "SocketCommunicator.run(world_size=3, fn=main);"
   ]
  },
  {
   "cell_type": "raw",
   "metadata": {
    "raw_mimetype": "text/restructuredtext"
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   "source": [
    ".. seealso:: :ref:`equality`, :ref:`less-than`"
   ]
  }
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