diff --git a/doc/LectureNotes/_build/.doctrees/environment.pickle b/doc/LectureNotes/_build/.doctrees/environment.pickle
index c6c70ce1d..906fc9a4c 100644
Binary files a/doc/LectureNotes/_build/.doctrees/environment.pickle and b/doc/LectureNotes/_build/.doctrees/environment.pickle differ
diff --git a/doc/LectureNotes/_build/.doctrees/exercisesweek35.doctree b/doc/LectureNotes/_build/.doctrees/exercisesweek35.doctree
index e4d37262e..3e8c9fa18 100644
Binary files a/doc/LectureNotes/_build/.doctrees/exercisesweek35.doctree and b/doc/LectureNotes/_build/.doctrees/exercisesweek35.doctree differ
diff --git a/doc/LectureNotes/_build/.doctrees/exercisesweek36.doctree b/doc/LectureNotes/_build/.doctrees/exercisesweek36.doctree
index f8892c80f..9aab23cea 100644
Binary files a/doc/LectureNotes/_build/.doctrees/exercisesweek36.doctree and b/doc/LectureNotes/_build/.doctrees/exercisesweek36.doctree differ
diff --git a/doc/LectureNotes/_build/html/_sources/exercisesweek35.ipynb b/doc/LectureNotes/_build/html/_sources/exercisesweek35.ipynb
index 886db99ef..403eab1f3 100644
--- a/doc/LectureNotes/_build/html/_sources/exercisesweek35.ipynb
+++ b/doc/LectureNotes/_build/html/_sources/exercisesweek35.ipynb
@@ -323,7 +323,7 @@
    "source": [
     "n = 100\n",
     "x = np.linspace(-3, 3, n)\n",
-    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(0, 1.0)"
+    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(n)"
    ]
   },
   {
diff --git a/doc/LectureNotes/_build/html/_sources/exercisesweek36.ipynb b/doc/LectureNotes/_build/html/_sources/exercisesweek36.ipynb
index ddf3e11e5..3dd1ad167 100644
--- a/doc/LectureNotes/_build/html/_sources/exercisesweek36.ipynb
+++ b/doc/LectureNotes/_build/html/_sources/exercisesweek36.ipynb
@@ -172,7 +172,7 @@
    "source": [
     "n = 100\n",
     "x = np.linspace(-3, 3, n)\n",
-    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(0, 0.1)"
+    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(n)"
    ]
   },
   {
diff --git a/doc/LectureNotes/_build/html/exercisesweek35.html b/doc/LectureNotes/_build/html/exercisesweek35.html
index 6ec0f14b5..b66673519 100644
--- a/doc/LectureNotes/_build/html/exercisesweek35.html
+++ b/doc/LectureNotes/_build/html/exercisesweek35.html
@@ -559,7 +559,7 @@ f_i =\sum_{j=0}^{n-1}a_{ij}x_j,
 <div class="cell_input docutils container">
 <div class="highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="n">n</span> <span class="o">=</span> <span class="mi">100</span>
 <span class="n">x</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">linspace</span><span class="p">(</span><span class="o">-</span><span class="mi">3</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="n">n</span><span class="p">)</span>
-<span class="n">y</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="n">x</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="mf">1.5</span> <span class="o">*</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="p">(</span><span class="n">x</span><span class="o">-</span><span class="mi">2</span><span class="p">)</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="n">np</span><span class="o">.</span><span class="n">random</span><span class="o">.</span><span class="n">normal</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mf">1.0</span><span class="p">)</span>
+<span class="n">y</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="n">x</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="mf">1.5</span> <span class="o">*</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="p">(</span><span class="n">x</span><span class="o">-</span><span class="mi">2</span><span class="p">)</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="n">np</span><span class="o">.</span><span class="n">random</span><span class="o">.</span><span class="n">normal</span><span class="p">(</span><span class="n">n</span><span class="p">)</span>
 </pre></div>
 </div>
 </div>
diff --git a/doc/LectureNotes/_build/html/exercisesweek36.html b/doc/LectureNotes/_build/html/exercisesweek36.html
index d61a64c3d..751e6cabd 100644
--- a/doc/LectureNotes/_build/html/exercisesweek36.html
+++ b/doc/LectureNotes/_build/html/exercisesweek36.html
@@ -477,7 +477,7 @@ defining a new cost function to be optimized, that is</p>
 <div class="cell_input docutils container">
 <div class="highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="n">n</span> <span class="o">=</span> <span class="mi">100</span>
 <span class="n">x</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">linspace</span><span class="p">(</span><span class="o">-</span><span class="mi">3</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="n">n</span><span class="p">)</span>
-<span class="n">y</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="n">x</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="mf">1.5</span> <span class="o">*</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="p">(</span><span class="n">x</span><span class="o">-</span><span class="mi">2</span><span class="p">)</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="n">np</span><span class="o">.</span><span class="n">random</span><span class="o">.</span><span class="n">normal</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mf">0.1</span><span class="p">)</span>
+<span class="n">y</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="n">x</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="mf">1.5</span> <span class="o">*</span> <span class="n">np</span><span class="o">.</span><span class="n">exp</span><span class="p">(</span><span class="o">-</span><span class="p">(</span><span class="n">x</span><span class="o">-</span><span class="mi">2</span><span class="p">)</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span> <span class="o">+</span> <span class="n">np</span><span class="o">.</span><span class="n">random</span><span class="o">.</span><span class="n">normal</span><span class="p">(</span><span class="n">n</span><span class="p">)</span>
 </pre></div>
 </div>
 </div>
diff --git a/doc/LectureNotes/_build/jupyter_execute/exercisesweek35.ipynb b/doc/LectureNotes/_build/jupyter_execute/exercisesweek35.ipynb
index e88352077..4c74687f4 100644
--- a/doc/LectureNotes/_build/jupyter_execute/exercisesweek35.ipynb
+++ b/doc/LectureNotes/_build/jupyter_execute/exercisesweek35.ipynb
@@ -323,7 +323,7 @@
    "source": [
     "n = 100\n",
     "x = np.linspace(-3, 3, n)\n",
-    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(0, 1.0)"
+    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(n)"
    ]
   },
   {
diff --git a/doc/LectureNotes/_build/jupyter_execute/exercisesweek36.ipynb b/doc/LectureNotes/_build/jupyter_execute/exercisesweek36.ipynb
index 820e0a768..2b233c4e1 100644
--- a/doc/LectureNotes/_build/jupyter_execute/exercisesweek36.ipynb
+++ b/doc/LectureNotes/_build/jupyter_execute/exercisesweek36.ipynb
@@ -172,7 +172,7 @@
    "source": [
     "n = 100\n",
     "x = np.linspace(-3, 3, n)\n",
-    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(0, 0.1)"
+    "y = np.exp(-x**2) + 1.5 * np.exp(-(x-2)**2) + np.random.normal(n)"
    ]
   },
   {