add examples notebook and some docstrings

daft_builder/pgm.py

@@ -1,7 +1,10 @@
+"""
+Core builder interfaces.
+
+"""
 import logging
 import itertools
 
-import matplotlib; matplotlib.use('Agg')
 import daft
 from toposort import toposort
 
@@ -131,8 +134,8 @@ def add_kwarg_defaults(self, symbol, kwargs):
             kwargs['name'] = name
 
         kwargs.setdefault('scale', 2)
-        if 'fixed' in kwargs:
-            kwargs['offset'] = (0, 10)
+        if 'fixed' in kwargs and 'offset' not in kwargs:
+            kwargs['offset'] = (0, -25) if self.placement.startswith('below') else (0, 10)
 
         return kwargs
 
@@ -436,7 +439,7 @@ def place(self):
         x_units = x + width
         y_units = y + height
 
-        # Need to expand further to accomodate plates, if present
+        # Need to expand further to accommodate plates, if present
         # Right now, we just assume plates are present all around.
         # TODO: actually figure out if plates are present and only expand if so.
         x_units += 0.3

daft_builder/utils.py

@@ -1,3 +1,9 @@
+"""
+Utility functions.
+
+"""
+
+
 def name_from_symbol(symbol):
     starts_with_modifier = symbol.startswith('$\\')
     symbol = symbol.strip('$').replace('\\', '')

tests/test_utils.py

@@ -1,9 +1,11 @@
+import matplotlib; matplotlib.use('Agg')
 import pytest
 
 from daft_builder import utils
 
 
 @pytest.mark.parametrize('symbol,expected', [
+    ("test", "test"),
     (r"$X$", "X"),
     (r"$\theta$", "theta"),
     (r"$\Sigma$", "Sigma"),