diff --git a/.gitignore b/.gitignore
index fcd2c40..94a077f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -109,3 +109,6 @@ venv.bak/
 *.bak
 ~$python_for_data_science.pptx
 ~$python_for_machine_learning.pptx
+
+# direnv configuration file
+.envrc
diff --git a/environment.yml b/environment.yml
index 6cbfb8d..9d75524 100644
--- a/environment.yml
+++ b/environment.yml
@@ -11,6 +11,6 @@ dependencies:
   - seaborn
   - holoviews
   - ipywidgets
-  - hyperopt
+    #  - hyperopt
 prefix: /home/gjb/miniconda3/envs/python_for_machine_learning
 
diff --git a/python_for_machine_learning.pptx b/python_for_machine_learning.pptx
index 99b63ee..0fbe839 100644
Binary files a/python_for_machine_learning.pptx and b/python_for_machine_learning.pptx differ