{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import struct\n",
    "import binascii"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "f_max_s = '7fefffffffffffff'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "b'\\x7f\\xef\\xff\\xff\\xff\\xff\\xff\\xff'\n"
     ]
    }
   ],
   "source": [
    "print(binascii.unhexlify(f_max_s))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "<class 'bytes'>\n"
     ]
    }
   ],
   "source": [
    "print(type(binascii.unhexlify(f_max_s)))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "(1.7976931348623157e+308,)\n"
     ]
    }
   ],
   "source": [
    "print(struct.unpack('>d', binascii.unhexlify(f_max_s)))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1.7976931348623157e+308\n"
     ]
    }
   ],
   "source": [
    "print(struct.unpack('>d', binascii.unhexlify(f_max_s))[0])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "<class 'float'>\n"
     ]
    }
   ],
   "source": [
    "print(type(struct.unpack('>d', binascii.unhexlify(f_max_s))[0]))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [],
   "source": [
    "def hex_to_double(s):\n",
    "    if s.startswith('0x'):\n",
    "        s = s[2:]\n",
    "    s = s.replace(' ', '')\n",
    "    return struct.unpack('>d', binascii.unhexlify(s))[0]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1.7976931348623157e+308\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_double('7fefffffffffffff'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1.7976931348623157e+308\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_double('0x7fefffffffffffff'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1.7976931348623157e+308\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_double('0x7fef ffff ffff ffff'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "42.195\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_double('0x4045 18f5 c28f 5c29'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "inf\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_double('7ff0000000000000'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "nan\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_double('7ff0000000000001'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "5e-324\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_double('0000000000000001'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [],
   "source": [
    "# print(hex_to_double('ffff ffff ffff ffff ff'))\n",
    "# error: unpack requires a buffer of 8 bytes"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [],
   "source": [
    "# print(hex_to_double('ffff ffff ffff ff'))\n",
    "# error: unpack requires a buffer of 8 bytes"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [],
   "source": [
    "def hex_to_float(s):\n",
    "    if s.startswith('0x'):\n",
    "        s = s[2:]\n",
    "    s = s.replace(' ', '')\n",
    "    return struct.unpack('>f', binascii.unhexlify(s))[0]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "42.19499969482422\n"
     ]
    }
   ],
   "source": [
    "print(hex_to_float('0x4228c7ae'))"
   ]
  }
 ],
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   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
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  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
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   "file_extension": ".py",
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   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
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