Restructured the code

atmospheric refraction example.ipynb

@@ -159,6 +159,42 @@
     "\n",
     "print ('The dispersion is %.03f +/- %.03f milli arc seconds' %(dispersion_obs, dispersion_unc))"
    ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "There are also some quick calculation functions defined in the `examples.py` file, if you just want to know the refractive index, the refraction or the dispersion at standard atmospheric conditions (`conditions='STANDARD'`) or at Cerro Armazones (`conditions='CERRO_ARMAZONES'`)."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Quick refractive index: 1.0002733131243147\n",
+      "Quick refraction: 40.697 arcsec\n",
+      "Quick dispersion: 31.019 mas\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Quick refractive index\n",
+    "nq = quick_refractive_index(l=1.49, conditions='STANDARD')\n",
+    "print('Quick refractive index: {}'.format(nq))\n",
+    "\n",
+    "# Quick refraction\n",
+    "rq = quick_refraction(l1, zenith_obs, conditions='CERRO_ARMAZONES') * 3.6e3\n",
+    "print('Quick refraction: {:.3f} arcsec'.format(rq))\n",
+    "\n",
+    "# Quick dispersion\n",
+    "dq = quick_dispersion(l1, l2, zenith_obs, conditions='CERRO_ARMAZONES') * 3.6e6\n",
+    "print('Quick dispersion: {:.3f} mas'.format(dq))\n"
+   ]
   }
  ],
  "metadata": {