{
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   "source": [
    "import math\n",
    "def calculate_iou(box1, box2):\n",
    "\n",
    "    # Calculate the (x1, y1, x2, y2) coordinates of the intersection of box1 and box2. Calculate its Area.\n",
    "    xi1 = max(box1[0], box2[0])\n",
    "    yi1 = max(box1[1], box2[1])\n",
    "    xi2 = min(box1[2], box2[2])\n",
    "    yi2 = min(box1[3], box2[3])\n",
    "    inter_area = max((xi2 - xi1), 0) * max((yi2 - yi1), 0)  # Max keeps into account not overlapping box\n",
    "\n",
    "    # Calculate the Union area by using Formula: Union(A,B) = A + B - Inter(A,B)\n",
    "    box1_area = (box1[2] - box1[0]) * (box1[3] - box1[1])\n",
    "    box2_area = (box2[2] - box2[0]) * (box2[3] - box2[1])\n",
    "    union_area = box1_area + box2_area - inter_area\n",
    "\n",
    "    # compute the IoU\n",
    "    iou = inter_area / union_area\n",
    "\n",
    "    return iou"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 64,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "15.0\n",
      "[8.450052369622647, 12.393410142113215, 88.45005236962265, 77.39341014211321]\n",
      "0.4850460596873889\n"
     ]
    }
   ],
   "source": [
    "x1 = 75\n",
    "y1 = 60\n",
    "\n",
    "box1 = [0, 0, x1, y1]\n",
    "alpha = math.atan2(110,75)  # good number\n",
    "diag = 15\n",
    "x_cateto = diag * math.cos(alpha)\n",
    "y_cateto = diag * math.sin(alpha)\n",
    "print(math.sqrt(x_cateto**2 + y_cateto**2))\n",
    "box2 = [x_cateto, y_cateto, x1 + x_cateto + 5, y1 + y_cateto+ 5]\n",
    "print(box2)\n",
    "print(calculate_iou(box1, box2))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
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