some alt text updates

zingale · zingale · commit dc0ba10af0ec · 2026-02-06T11:41:30.000-05:00
diff --git a/content/09-packages/python-packages.md b/content/09-packages/python-packages.md
@@ -9,7 +9,7 @@ The python packaging system is constantly evolving, and the current recommendati
 of tools is list here: https://packaging.python.org/en/latest/guides/tool-recommendations/
 ```
 
-![xkcd](python_environment.png)
+![xkcd comic on python packaging chaos](python_environment.png)
 
 (from https://xkcd.com)
 
diff --git a/content/11-machine-learning/neural-net-basics.md b/content/11-machine-learning/neural-net-basics.md
@@ -43,7 +43,7 @@ Our goal is to determine the matrix elements of ${\bf A}$.
 
 We can visualize a neural network as:
 
-![NN diagram](nn_fig.png)
+![neural network diagram showing nodes in layers linked](nn_fig.png)
 
 * Neural networks are divided into _layers_
 
diff --git a/content/11-machine-learning/neural-net-hidden.md b/content/11-machine-learning/neural-net-hidden.md
@@ -3,7 +3,7 @@
 
  We can get better performance from a neural network by adding a hidden layer:
 
-![hidden layers](nn_fig_hidden.png)
+![neutron network diagram showing a single hidden layer](nn_fig_hidden.png)
 
 The size of the hidden layer is independent of the size of the input and output
 layers.  In this case, we have a hidden layer that is larger
diff --git a/content/Introduction.md b/content/Introduction.md
@@ -1,6 +1,6 @@
 # PHY 546: Python for Scientific Computing
 
-![xkcd](01-python/python.png)
+![xkcd python cartoon](01-python/python.png)
 
 (from https://xkcd.com)
 
diff --git a/requirements.txt b/requirements.txt
@@ -1,16 +1,21 @@
+# docs
 jupyter-book<2
+git+https://github.com/executablebooks/sphinx-book-theme.git
+sphinx-copybutton
+sphinx-prompt
+jupyterlab_myst
+jupyterbook_patches
+
+# core python
 matplotlib
-#basemap
 numpy
 sympy
 scipy
+
+# ML
 keras
-#tensorflow
 torch
 pydot
 graphviz
 scikit-learn
-sphinx-copybutton
-sphinx-prompt
-jupyterlab_myst
-jupyterbook_patches
+
