update toc and test linking

docs/_toc.yml

@@ -12,7 +12,8 @@ parts:
   - file: example_notebooks/workflow_minimal.ipynb
   - file: input_files
   - file: theory
-  - title: Algorithmic implementation
+  - file: algo
+    title: Algorithmic implementation
     sections:
     - file: algo1
     - file: algo2

docs/algo.md

@@ -0,0 +1,3 @@
+# Algorithmic Implementations
+
+The following sections connect the underlying [theory](theory:theory_base) with the variables and data structures presented in [](data-structure).

docs/classes-datastructures.md

@@ -1,3 +1,4 @@
+(data-structure)=
 # Classes and data structures
 
 ## Classes

docs/theory.ipynb

@@ -0,0 +1,33 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "(theory:theory_base)=\n",
+    "# Theory"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "language_info": {
+   "name": "python"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}