examples: updated notebooks

Changes:
- formatted imports
- removed obsolete np.array call in np.hstack

Author: Littie28

examples/01-surface_intersections.ipynb

@@ -25,8 +25,12 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from hazy import Frame, Point, Vector\n",
-    "from dataclasses import dataclass"
+    "from dataclasses import dataclass\n",
+    "\n",
+    "import numpy as np\n",
+    "import matplotlib.pyplot as plt\n",
+    "\n",
+    "from hazy import Frame, Point, Vector"
    ]
   },
   {
@@ -218,8 +222,6 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "import numpy as np\n",
-    "\n",
     "distance_traveled = (intersection_global - simple_ray.origin.to_global()).magnitude\n",
     "print(f\"Distance ray traveled: {distance_traveled:.2f} units\")\n",
     "\n",
@@ -269,8 +271,6 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "import matplotlib.pyplot as plt\n",
-    "\n",
     "complex_ray_frame = (\n",
     "    root.make_child(\"complex_ray\").translate(x=-2, z=1).rotate_euler(y=10, degrees=True)\n",
     ")\n",

examples/02-frame-hierarchies.ipynb

@@ -114,7 +114,7 @@
     "    end_point = laser.origin + laser.direction * (i + 1) / 5\n",
     "    end_global = end_point.to_global()\n",
     "\n",
-    "    laser_line = np.vstack([np.array(origin_global), np.array(end_global)])\n",
+    "    laser_line = np.vstack([origin_global, end_global])\n",
     "\n",
     "    ax.plot(*laser_line[:, :2].T, color=colors[i], linewidth=2, alpha=0.8)\n",
     "\n",