Merge pull request #21223 from MaqOwais/image_correction

Fixes (solvers) : Removed Attribute error, type error
sympy · Apr 5, 2021 · 7053279 · 7053279
2 parents 38b621a + b6985fe
commit 7053279
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Showing 2 changed files with 34 additions and 9 deletions.
diff --git a/sympy/solvers/solveset.py b/sympy/solvers/solveset.py
@@ -3198,15 +3198,14 @@ def _solve_using_known_values(result, solver):
             result = _new_order_result(result, eq)
             for res in result:
                 got_symbol = set()  # symbols solved in one iteration
-                if soln_imageset:
-                    # find the imageset and use its expr.
-                    for key_res, value_res in res.items():
-                        if isinstance(value_res, ImageSet):
-                            res[key_res] = value_res.lamda.expr
-                            original_imageset[key_res] = value_res
-                            dummy_n = value_res.lamda.expr.atoms(Dummy).pop()
-                            (base,) = value_res.base_sets
-                            imgset_yes = (dummy_n, base)
+                # find the imageset and use its expr.
+                for key_res, value_res in res.items():
+                    if isinstance(value_res, ImageSet):
+                        res[key_res] = value_res.lamda.expr
+                        original_imageset[key_res] = value_res
+                        dummy_n = value_res.lamda.expr.atoms(Dummy).pop()
+                        (base,) = value_res.base_sets
+                        imgset_yes = (dummy_n, base)
                 # update eq with everything that is known so far
                 eq2 = eq.subs(res).expand()
                 unsolved_syms = _unsolved_syms(eq2, sort=True)

diff --git a/sympy/solvers/tests/test_solveset.py b/sympy/solvers/tests/test_solveset.py
@@ -1,4 +1,5 @@
 from sympy.core.containers import Tuple
+from sympy.core.compatibility import ordered
 from sympy.core.function import (Function, Lambda, nfloat, diff)
 from sympy.core.mod import Mod
 from sympy.core.numbers import (E, I, Rational, oo, pi)
@@ -1700,6 +1701,31 @@ def test_solve_nonlinear_trans():
     assert nonlinsolve([x**2 - y**2/exp(x)], [x, y]) == soln4
 
 
+def test_issue_19050():
+    # test_issue_19050 --> TypeError removed
+    assert dumeq(nonlinsolve([x + y, sin(y)], [x, y]),
+        FiniteSet((ImageSet(Lambda(n, -2*n*pi), S.Integers), ImageSet(Lambda(n, 2*n*pi), S.Integers)),\
+             (ImageSet(Lambda(n, -2*n*pi - pi), S.Integers), ImageSet(Lambda(n, 2*n*pi + pi), S.Integers))))
+    assert dumeq(nonlinsolve([x + y, sin(y) + cos(y)], [x, y]),
+        FiniteSet((ImageSet(Lambda(n, -2*n*pi - 3*pi/4), S.Integers), ImageSet(Lambda(n, 2*n*pi + 3*pi/4), S.Integers)), \
+            (ImageSet(Lambda(n, -2*n*pi - 7*pi/4), S.Integers), ImageSet(Lambda(n, 2*n*pi + 7*pi/4), S.Integers))))
+
+
+def test_issue_16618():
+    # AttributeError is removed !
+    # have to remove the redundancy
+    _n = Dummy('n')
+    eqn = [sin(x)*sin(y), cos(x)*cos(y) - 1]
+    ans = FiniteSet((x, 2*n*pi), (2*n*pi, y), (x, 2*n*pi + pi), (2*n*pi + pi, y),\
+        (x, 2*_n*pi), (2*_n*pi, y), (x, 2*_n*pi + pi), (2*_n*pi + pi, y))
+    sol = nonlinsolve(eqn, [x, y])
+
+    for i0, j0 in zip(ordered(sol), ordered(ans)):
+        assert len(i0) == len(j0) == 2
+        assert all(a.dummy_eq(b) for a, b in zip(i0, j0))
+    assert len(sol) == len(ans)
+
+
 def test_issue_5132_1():
     system = [sqrt(x**2 + y**2) - sqrt(10), x + y - 4]
     assert nonlinsolve(system, [x, y]) == FiniteSet((1, 3), (3, 1))