Merge pull request #460 from qiboteam/fixnumpy

normalizing probs
qiboteam · Sep 8, 2021 · 4073ce9 · 4073ce9
2 parents 9af4e77 + fc333eb
commit 4073ce9
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Showing 2 changed files with 4 additions and 2 deletions.
diff --git a/src/qibo/backends/__init__.py b/src/qibo/backends/__init__.py
@@ -60,7 +60,8 @@ def __init__(self):
         # Create the default active backend
         if "QIBO_BACKEND" in os.environ:  # pragma: no cover
             self.active_backend = os.environ.get("QIBO_BACKEND")
-        self.active_backend = active_backend
+        else:
+            self.active_backend = active_backend
 
         # raise performance warning if qibojit and qibotf are not available
         self.show_config()

diff --git a/src/qibo/backends/numpy.py b/src/qibo/backends/numpy.py
@@ -218,7 +218,8 @@ def sample_shots(self, probs, nshots):
     def sample_frequencies(self, probs, nshots):
         from qibo.config import SHOT_BATCH_SIZE
         def update_frequencies(nsamples, frequencies):
-            samples = self.random.choice(range(len(probs)), size=nsamples, p=probs)
+            samples = self.random.choice(
+                range(len(probs)), size=nsamples, p=probs/self.backend.sum(probs))
             res, counts = self.backend.unique(samples, return_counts=True)
             frequencies[res] += counts
             return frequencies