Added two simple games with chance nodes: nature playing first and last

Author: d-kad

tests/test_games/nature-leaves.efg

@@ -0,0 +1,18 @@
+EFG 2 R "2 player game: chance plays last" { "Player 1" "Player 2" }
+""
+
+p "" 1 1 "" { "B" "T" } 0
+p "" 2 1 "" { "r" "l" } 0
+c "" 1 "" { "1" 1/2 "2" 1/2 } 0
+t "" 1 "Outcome 1" { 0, 0 }
+t "" 2 "Outcome 2" { -2, -2 }
+c "" 2 "" { "1" 1/2 "2" 1/2 } 0
+t "" 3 "Outcome 3" { 3, 3 }
+t "" 4 "Outcome 4" { 1, 1 }
+p "" 2 2 "" { "R" "L" } 0
+c "" 3 "" { "1" 1/2 "2" 1/2 } 0
+t "" 5 "Outcome 5" { 0, 4 }
+t "" 6 "Outcome 6" { 0, 2 }
+c "" 4 "" { "1" 1/2 "2" 1/2 } 0
+t "" 7 "Outcome 7" { 0, 5 }
+t "" 8 "Outcome 8" { 0, 3 }

tests/test_games/nature-rooted.efg

@@ -0,0 +1,18 @@
+EFG 2 R "2 player game: chance plays at the root" { "Player 1" "Player 2" }
+""
+
+c "" 1 "" { "1" 1/2 "2" 1/2 } 0
+p "" 1 1 "" { "B" "T" } 0
+p "" 2 2 "" { "r" "l" } 0
+t "" 1 "Outcome 1" { 0, 0 }
+t "" 2 "Outcome 2" { 3, 3 }
+p "" 2 1 "" { "R" "L" } 0
+t "" 3 "Outcome 3" { 0, 4 }
+t "" 4 "Outcome 4" { 0, 5 }
+p "" 1 1 "" { "B" "T" } 0
+p "" 2 2 "" { "r" "l" } 0
+t "" 5 "Outcome 5" { -2, -2 }
+t "" 6 "Outcome 6" { 1, 1 }
+p "" 2 1 "" { "R" "L" } 0
+t "" 7 "Outcome 7" { 0, 2 }
+t "" 8 "Outcome 8" { 0, 3 }

tests/test_rsf.py

@@ -44,15 +44,6 @@
                 np.array([[[1, 1], [0, 1]], [[2, 0], [2, 0]]]),
             ],
         ),
-        # Myerson 2-card poker; game with chance node
-        (
-            games.read_from_file("myerson_2_card_poker.efg"),  # CHANGE
-            [["11", "12", "21", "22"], ["1", "2"]],
-            [
-                np.array([[-1, 0], ["-1/2", -1], ["-5/2", -1], [-2, -2]]),
-                np.array([[1, 0], ["1/2", 1], ["5/2", 1], [2, 2]]),
-            ],
-        ),
         # 2-player (zero-sum) game with reduction for both players and generic payoffs
         (
             games.create_reduction_generic_payoffs_efg(),
@@ -136,6 +127,34 @@
                 ),
             ],
         ),
+        # N A T U R E
+        # Myerson 2-card poker; game with chance playing at the root
+        (
+            games.read_from_file("myerson_2_card_poker.efg"),  # CHANGE
+            [["11", "12", "21", "22"], ["1", "2"]],
+            [
+                np.array([[-1, 0], ["-1/2", -1], ["-5/2", -1], [-2, -2]]),
+                np.array([[1, 0], ["1/2", 1], ["5/2", 1], [2, 2]]),
+            ],
+        ),
+        # Nature playing at the root
+        (
+            games.read_from_file("nature-rooted.efg"),
+            [["1", "2"], ["11", "12", "21", "22"]],
+            [
+                np.array([[-1, -1, 2, 2], [0, 0, 0, 0]]),
+                np.array([[-1, -1, 2, 2], [3, 4, 3, 4]]),
+            ],
+        ),
+        # Nature playing last determining the payoffs
+        (
+            games.read_from_file("nature-leaves.efg"),
+            [["1", "2"], ["11", "12", "21", "22"]],
+            [
+                np.array([[-1, -1, 2, 2], [0, 0, 0, 0]]),
+                np.array([[-1, -1, 2, 2], [3, 4, 3, 4]]),
+            ],
+        ),
     ],
 )
 def test_reduced_strategic_form(