fix test sinkhorn div

Author: Kilian Fatras

ot/bregman.py

@@ -1587,8 +1587,13 @@ def empirical_sinkhorn_divergence(X_s, X_t, reg, a=None, b=None, metric='sqeucli
         log['log_sinkhorn_b'] = log_b
 
         return max(0, sinkhorn_div), log
+
     else:
-        sinkhorn_div = (empirical_sinkhorn2(X_s, X_t, reg, a, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9, verbose=verbose, log=log, **kwargs) -
-                        1 / 2 * empirical_sinkhorn2(X_s, X_s, reg, a, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9, verbose=verbose, log=log, **kwargs) -
-                        1 / 2 * empirical_sinkhorn2(X_t, X_t, reg, a, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9, verbose=verbose, log=log, **kwargs))
+        sinkhorn_loss_ab = empirical_sinkhorn2(X_s, X_t, reg, a, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9, verbose=verbose, log=log, **kwargs)
+
+        sinkhorn_loss_a = empirical_sinkhorn2(X_s, X_s, reg, a, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9, verbose=verbose, log=log, **kwargs)
+
+        sinkhorn_loss_b = empirical_sinkhorn2(X_t, X_t, reg, a, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9, verbose=verbose, log=log, **kwargs)
+
+        sinkhorn_div = sinkhorn_loss_ab - 1 / 2 * (sinkhorn_loss_a + sinkhorn_loss_b)
         return max(0, sinkhorn_div)

test/test_bregman.py

@@ -241,11 +241,13 @@ def test_empirical_sinkhorn_divergence():
     M_t = ot.dist(X_t, X_t)
 
     emp_sinkhorn_div = ot.bregman.empirical_sinkhorn_divergence(X_s, X_t, 1)
-    sinkhorn_div = (2 * ot.sinkhorn2(a, b, M, 1) - ot.sinkhorn2(a, a, M_s, 1) -
-                    ot.sinkhorn2(b, b, M_t, 1))
+    sinkhorn_div = (ot.sinkhorn2(a, b, M, 1) - 1 / 2 * ot.sinkhorn2(a, a, M_s, 1) - 1 / 2 * ot.sinkhorn2(b, b, M_t, 1))
 
     emp_sinkhorn_div_log, log_es = ot.bregman.empirical_sinkhorn_divergence(X_s, X_t, 0.1, log=True)
-    sinkhorn_div_log, log_s = ot.sinkhorn(a, b, M, 0.1, log=True)
+    sink_div_log, log_s = ot.sinkhorn2(a, b, M, 1)
+    sink_div_log_a, log_s_a = ot.sinkhorn2(a, a, M_s, 1)
+    sink_div_log_b, log_s_b = ot.sinkhorn2(b, b, M_t, 1)
+    sink_div_log = sink_div_log - 1 / 2 * (sink_div_log_a + sink_div_log_b)
 
     # check constratints
     np.testing.assert_allclose(