diff --git a/ipython/FittingData.ipynb b/ipython/FittingData.ipynb
index 65f52d7..a147d95 100644
--- a/ipython/FittingData.ipynb
+++ b/ipython/FittingData.ipynb
@@ -368,9 +368,9 @@
       "    x = (X*data).sum()/total\n",
       "    y = (Y*data).sum()/total\n",
       "    col = data[:, int(y)]\n",
-      "    width_x = np.sqrt(np.abs((np.arange(col.size)-y)**2*col).sum()/col.sum())\n",
+      "    width_x = np.sqrt(np.abs((np.arange(col.size)-x)**2*col).sum()/col.sum())\n",
       "    row = data[int(x), :]\n",
-      "    width_y = np.sqrt(np.abs((np.arange(row.size)-x)**2*row).sum()/row.sum())\n",
+      "    width_y = np.sqrt(np.abs((np.arange(row.size)-y)**2*row).sum()/row.sum())\n",
       "    height = data.max()\n",
       "    return height, x, y, width_x, width_y\n",
       "\n",