from sympy.sandbox.indexed_integrals import IndexedIntegral from sympy.core.symbol import symbols from sympy.functions.elementary.trigonometric import (cos, sin) from sympy.tensor.indexed import (Idx, IndexedBase) def test_indexed_integrals(): A = IndexedBase('A') i, j = symbols('i j', integer=True) a1, a2 = symbols('a1:3', cls=Idx) assert isinstance(a1, Idx) assert IndexedIntegral(1, A[i]).doit() == A[i] assert IndexedIntegral(A[i], A[i]).doit() == A[i] ** 2 / 2 assert IndexedIntegral(A[j], A[i]).doit() == A[i] * A[j] assert IndexedIntegral(A[i] * A[j], A[i]).doit() == A[i] ** 2 * A[j] / 2 assert IndexedIntegral(sin(A[i]), A[i]).doit() == -cos(A[i]) assert IndexedIntegral(sin(A[j]), A[i]).doit() == sin(A[j]) * A[i] assert IndexedIntegral(1, A[a1]).doit() == A[a1] assert IndexedIntegral(A[a1], A[a1]).doit() == A[a1] ** 2 / 2 assert IndexedIntegral(A[a2], A[a1]).doit() == A[a1] * A[a2] assert IndexedIntegral(A[a1] * A[a2], A[a1]).doit() == A[a1] ** 2 * A[a2] / 2 assert IndexedIntegral(sin(A[a1]), A[a1]).doit() == -cos(A[a1]) assert IndexedIntegral(sin(A[a2]), A[a1]).doit() == sin(A[a2]) * A[a1]