updated for API2 and did a little cleanup.

Author: jwoehr

games/game_engines/quantum_slot/quantum_slot.py

@@ -1,15 +1,17 @@
+import threading
+import os
 import json
 from urllib.parse import urlencode
 from urllib.request import urlopen
-from qiskit import *
-from qiskit.tools.monitor import job_monitor
-import ipywidgets as widgets
 from IPython.display import display
-import threading
-import os
+import ipywidgets as widgets
+from qiskit import IBMQ, execute, QuantumCircuit, QuantumRegister, ClassicalRegister, BasicAer
+from qiskit.tools.monitor import job_monitor
+
 script_dir = os.path.dirname(__file__)
 
-IBMQ.load_accounts(hub=None)
+MY_PROVIDER = IBMQ.load_account()
+
 
 __all__ = ['quantum_slot_machine']
 
@@ -101,7 +103,7 @@ def compute_payout(ints, qslot):
     elif all([x == 0 for x in ints]):
         value = 80
     # two bells
-    elif sum([x == 0 for x in ints])== 2:
+    elif sum([x == 0 for x in ints]) == 2:
         value = 5
     # two bells
     elif sum([x == 0 for x in ints]) == 1:
@@ -110,7 +112,7 @@ def compute_payout(ints, qslot):
         value = 0
     if value:
         update_credits(value, qslot)
-    
+
     # if no credits left
     if qslot.children[0]._credits <= 0:
         qslot.children[1].children[1].value = front_str + \
@@ -131,11 +133,19 @@ def pull_slot(b):
     if alive:
         b.disabled = False
 
+def choose_backend():
+    from qiskit.providers.ibmq import least_busy
+    large_enough_devices = MY_PROVIDER.backends(
+        filters=lambda x: x.configuration().n_qubits >= 3
+        and not x.configuration().simulator)
+    return least_busy(large_enough_devices)
+
 # generate new ibm q values
 def get_ibmq_ints(qslot):
     qslot.children[1].children[0].options = ['qasm_simulator', 'ANU QRNG']
     qslot.children[1].children[0].value = 'qasm_simulator'
-    back = IBMQ.get_backend('ibmq_5_tenerife')
+#    back = MY_PROVIDER.get_backend('ibmq_essex')
+    back = choose_backend()
     q = QuantumRegister(3, name='q')
     c = ClassicalRegister(3, name='c')
     qc = QuantumCircuit(q, c)
@@ -310,6 +320,5 @@ def get_ibmq_ints(qslot):
 
 opts = widgets.HBox(children=[solver, payout, out],
                     layout=widgets.Layout(width='100%',
-                                         justify_content='center',
-                                         border='2px solid black'))
-
+                                          justify_content='center',
+                                          border='2px solid black'))

games/quantum_slot_machine.ipynb

@@ -18,7 +18,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 2,
+   "execution_count": 1,
    "metadata": {
     "ExecuteTime": {
      "end_time": "2018-12-28T15:54:29.168824Z",
@@ -30,7 +30,7 @@
     {
      "data": {
       "application/vnd.jupyter.widget-view+json": {
-       "model_id": "d7b78a19e7d946c7b64c90cafb555fd1",
+       "model_id": "a800b89078844bb399a15d512fda176a",
        "version_major": 2,
        "version_minor": 0
       },
@@ -82,8 +82,8 @@
     "Uses the local qasm simulator in Qiskit terra to pseudo-randomly generate bit strings from a single-shot of quantum circuit that consists of Hadamard gates on nine different qubits followed by measurements.\n",
     "\n",
     "\n",
-    "* **ibmq_5_tenerife**\n",
-    "Computes $300$ shots of a three-qubit variant of the same circuit used in the simulator.  This is because only the `ibmq_5_tenerife` allows for accessing the `memory` of the backend, as opposed to computing the counts for all the shots.  Although pre-computing random values is not ideal as an evil-doer may be able to read the numbers, on IBM Q devices, it is best to compute a lot of values at once and then cache them.  After running once, this selection will allow you to use the machine $100$ times.\n",
+    "* **Computation**\n",
+    "Computes $300$ shots of a three-qubit variant of the same circuit used in the simulator. After running once, this selection will allow you to use the machine $100$ times.\n",
     "\n",
     "\n",
     "* **ANU QRNG**\n",
@@ -117,7 +117,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.0"
+   "version": "3.6.8"
   }
  },
  "nbformat": 4,