Adjust the way plot method uses MPL (#75)

* Add a description

* default agg use for mpl

* use agg adjust

* use agg trigger adjust

* udpate tests

peartree/__version__.py

@@ -1 +1 @@
-__version__ = '0.4.1'
+__version__ = '0.4.2'

peartree/paths.py

@@ -168,6 +168,14 @@ def load_synthetic_network_as_graph(
         connection_threshold: float=50.0,
         walk_speed_kmph: float=4.5,
         impute_walk_transfers: bool=True):
+    """
+    Convert a formatter transit FeatureCollection into a directed network graph.
+
+    Utilizing a correctly formatted transit FeatureCollection, generate a
+    directed networ graph (or add to an existing one), based off of features
+    included in the reference_geojson parameter.
+    """
+
 
     # Generate a random name for name if it is None
     if not name:

peartree/plot.py

@@ -1,18 +1,16 @@
 import os
 
-import matplotlib
 import networkx as nx
 import osmnx as ox
 
-# Check if the display has already been set and, if not...
-cmd = 'python -c "import matplotlib.pyplot as plt;plt.figure()"'
-check = os.system(cmd)
-if check != 0:
-    # Force matplotlib to not use any Xwindows backend
-    matplotlib.use('Agg')
 
+def generate_plot(G: nx.MultiDiGraph, use_agg=False):
+    # Load matplotlib only when plot requested
+    import matplotlib  # noqa
+    if use_agg:
+        # Force matplotlib to not use any Xwindows backend
+        matplotlib.use('Agg')
 
-def generate_plot(G: nx.MultiDiGraph):
     # TODO: Build out custom plotting configurations but,
     #       in the meantime, use OSMnx's plotting configurations
     #       since they work well for the current use case and I

tests/test_plot.py

@@ -17,4 +17,4 @@ def test_feed_to_graph_plot():
 
     G = load_feed_as_graph(feed, start, end)
 
-    fig, ax = generate_plot(G)
+    fig, ax = generate_plot(G, use_agg=True)