Add new sections.

Author: cuihantao

pct/_toc.yml

@@ -16,5 +16,7 @@ chapters:
 - file: modules/04/intro.md
   sections:
   - file: modules/04/linear-equations.ipynb
+  - file: modules/04/nonlinear-equations.ipynb
+  - file: modules/04/acceleration.ipynb
 - file: notebooks
 - file: markdown-notebooks

pct/modules/04/acceleration.ipynb

@@ -0,0 +1,25 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Numerical Acceleration"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "language_info": {
+   "name": "python"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}