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.mailmap

@@ -548,7 +548,7 @@ Elias Basler <e.e.basler@protonmail.com>
 Elisha Hollander <just4now666666@gmail.com> donno2048 <just4now666666@gmail.com>
 Elliot Marshall <Marshall2389@gmail.com> <marshall2389@gmail.com>
 Elrond der Elbenfuerst <elrond+sympy.org@samba-tng.org>
-Emile <emile.fourcin1@gmail.com>
+Emile Fourcini <emile.fourcin1@gmail.com> Emile <emile.fourcin1@gmail.com>
 Emma Hogan <ehogan@gemini.edu>
 Enric Florit <efz1005@gmail.com>
 Eric Demer <demer@mailbox.org>

sympy/calculus/tests/test_util.py

@@ -286,10 +286,10 @@ def test_is_convex():
     assert is_convex(x**2, x, domain=Interval(0, oo)) == True
     assert is_convex(1/x**3, x, domain=Interval.Lopen(0, oo)) == True
     assert is_convex(-1/x**3, x, domain=Interval.Ropen(-oo, 0)) == True
-    assert is_convex(log(x),x) == False
-    assert is_convex(x**2+y**2,x,y)==True
-    assert is_convex(cos(x)+cos(y),x)==False
-    assert is_convex(8*x**2-2*y**2,x,y)==False
+    assert is_convex(log(x) ,x) == False
+    assert is_convex(x**2+y**2, x, y) == True
+    assert is_convex(cos(x) + cos(y), x) == False
+    assert is_convex(8*x**2 - 2*y**2, x, y) == False
 
 
 def test_stationary_points():

sympy/calculus/util.py

@@ -747,8 +747,7 @@ def is_convex(f, *syms, domain=S.Reals):
 
     """
     if len(syms) > 1 :
-        a = hessian(f,syms)
-        return a.is_positive_semidefinite
+        return hessian(f, syms).is_positive_semidefinite
     from sympy.solvers.inequalities import solve_univariate_inequality
     f = _sympify(f)
     var = syms[0]