Traktor/myenv/Lib/site-packages/sympy/tensor/tests/test_index_methods.py
2024-05-26 05:12:46 +02:00

228 lines
6.9 KiB
Python

from sympy.core import symbols, S, Pow, Function
from sympy.functions import exp
from sympy.testing.pytest import raises
from sympy.tensor.indexed import Idx, IndexedBase
from sympy.tensor.index_methods import IndexConformanceException
from sympy.tensor.index_methods import (get_contraction_structure, get_indices)
def test_trivial_indices():
x, y = symbols('x y')
assert get_indices(x) == (set(), {})
assert get_indices(x*y) == (set(), {})
assert get_indices(x + y) == (set(), {})
assert get_indices(x**y) == (set(), {})
def test_get_indices_Indexed():
x = IndexedBase('x')
i, j = Idx('i'), Idx('j')
assert get_indices(x[i, j]) == ({i, j}, {})
assert get_indices(x[j, i]) == ({j, i}, {})
def test_get_indices_Idx():
f = Function('f')
i, j = Idx('i'), Idx('j')
assert get_indices(f(i)*j) == ({i, j}, {})
assert get_indices(f(j, i)) == ({j, i}, {})
assert get_indices(f(i)*i) == (set(), {})
def test_get_indices_mul():
x = IndexedBase('x')
y = IndexedBase('y')
i, j = Idx('i'), Idx('j')
assert get_indices(x[j]*y[i]) == ({i, j}, {})
assert get_indices(x[i]*y[j]) == ({i, j}, {})
def test_get_indices_exceptions():
x = IndexedBase('x')
y = IndexedBase('y')
i, j = Idx('i'), Idx('j')
raises(IndexConformanceException, lambda: get_indices(x[i] + y[j]))
def test_scalar_broadcast():
x = IndexedBase('x')
y = IndexedBase('y')
i, j = Idx('i'), Idx('j')
assert get_indices(x[i] + y[i, i]) == ({i}, {})
assert get_indices(x[i] + y[j, j]) == ({i}, {})
def test_get_indices_add():
x = IndexedBase('x')
y = IndexedBase('y')
A = IndexedBase('A')
i, j, k = Idx('i'), Idx('j'), Idx('k')
assert get_indices(x[i] + 2*y[i]) == ({i}, {})
assert get_indices(y[i] + 2*A[i, j]*x[j]) == ({i}, {})
assert get_indices(y[i] + 2*(x[i] + A[i, j]*x[j])) == ({i}, {})
assert get_indices(y[i] + x[i]*(A[j, j] + 1)) == ({i}, {})
assert get_indices(
y[i] + x[i]*x[j]*(y[j] + A[j, k]*x[k])) == ({i}, {})
def test_get_indices_Pow():
x = IndexedBase('x')
y = IndexedBase('y')
A = IndexedBase('A')
i, j, k = Idx('i'), Idx('j'), Idx('k')
assert get_indices(Pow(x[i], y[j])) == ({i, j}, {})
assert get_indices(Pow(x[i, k], y[j, k])) == ({i, j, k}, {})
assert get_indices(Pow(A[i, k], y[k] + A[k, j]*x[j])) == ({i, k}, {})
assert get_indices(Pow(2, x[i])) == get_indices(exp(x[i]))
# test of a design decision, this may change:
assert get_indices(Pow(x[i], 2)) == ({i}, {})
def test_get_contraction_structure_basic():
x = IndexedBase('x')
y = IndexedBase('y')
i, j = Idx('i'), Idx('j')
assert get_contraction_structure(x[i]*y[j]) == {None: {x[i]*y[j]}}
assert get_contraction_structure(x[i] + y[j]) == {None: {x[i], y[j]}}
assert get_contraction_structure(x[i]*y[i]) == {(i,): {x[i]*y[i]}}
assert get_contraction_structure(
1 + x[i]*y[i]) == {None: {S.One}, (i,): {x[i]*y[i]}}
assert get_contraction_structure(x[i]**y[i]) == {None: {x[i]**y[i]}}
def test_get_contraction_structure_complex():
x = IndexedBase('x')
y = IndexedBase('y')
A = IndexedBase('A')
i, j, k = Idx('i'), Idx('j'), Idx('k')
expr1 = y[i] + A[i, j]*x[j]
d1 = {None: {y[i]}, (j,): {A[i, j]*x[j]}}
assert get_contraction_structure(expr1) == d1
expr2 = expr1*A[k, i] + x[k]
d2 = {None: {x[k]}, (i,): {expr1*A[k, i]}, expr1*A[k, i]: [d1]}
assert get_contraction_structure(expr2) == d2
def test_contraction_structure_simple_Pow():
x = IndexedBase('x')
y = IndexedBase('y')
i, j, k = Idx('i'), Idx('j'), Idx('k')
ii_jj = x[i, i]**y[j, j]
assert get_contraction_structure(ii_jj) == {
None: {ii_jj},
ii_jj: [
{(i,): {x[i, i]}},
{(j,): {y[j, j]}}
]
}
ii_jk = x[i, i]**y[j, k]
assert get_contraction_structure(ii_jk) == {
None: {x[i, i]**y[j, k]},
x[i, i]**y[j, k]: [
{(i,): {x[i, i]}}
]
}
def test_contraction_structure_Mul_and_Pow():
x = IndexedBase('x')
y = IndexedBase('y')
i, j, k = Idx('i'), Idx('j'), Idx('k')
i_ji = x[i]**(y[j]*x[i])
assert get_contraction_structure(i_ji) == {None: {i_ji}}
ij_i = (x[i]*y[j])**(y[i])
assert get_contraction_structure(ij_i) == {None: {ij_i}}
j_ij_i = x[j]*(x[i]*y[j])**(y[i])
assert get_contraction_structure(j_ij_i) == {(j,): {j_ij_i}}
j_i_ji = x[j]*x[i]**(y[j]*x[i])
assert get_contraction_structure(j_i_ji) == {(j,): {j_i_ji}}
ij_exp_kki = x[i]*y[j]*exp(y[i]*y[k, k])
result = get_contraction_structure(ij_exp_kki)
expected = {
(i,): {ij_exp_kki},
ij_exp_kki: [{
None: {exp(y[i]*y[k, k])},
exp(y[i]*y[k, k]): [{
None: {y[i]*y[k, k]},
y[i]*y[k, k]: [{(k,): {y[k, k]}}]
}]}
]
}
assert result == expected
def test_contraction_structure_Add_in_Pow():
x = IndexedBase('x')
y = IndexedBase('y')
i, j, k = Idx('i'), Idx('j'), Idx('k')
s_ii_jj_s = (1 + x[i, i])**(1 + y[j, j])
expected = {
None: {s_ii_jj_s},
s_ii_jj_s: [
{None: {S.One}, (i,): {x[i, i]}},
{None: {S.One}, (j,): {y[j, j]}}
]
}
result = get_contraction_structure(s_ii_jj_s)
assert result == expected
s_ii_jk_s = (1 + x[i, i]) ** (1 + y[j, k])
expected_2 = {
None: {(x[i, i] + 1)**(y[j, k] + 1)},
s_ii_jk_s: [
{None: {S.One}, (i,): {x[i, i]}}
]
}
result_2 = get_contraction_structure(s_ii_jk_s)
assert result_2 == expected_2
def test_contraction_structure_Pow_in_Pow():
x = IndexedBase('x')
y = IndexedBase('y')
z = IndexedBase('z')
i, j, k = Idx('i'), Idx('j'), Idx('k')
ii_jj_kk = x[i, i]**y[j, j]**z[k, k]
expected = {
None: {ii_jj_kk},
ii_jj_kk: [
{(i,): {x[i, i]}},
{
None: {y[j, j]**z[k, k]},
y[j, j]**z[k, k]: [
{(j,): {y[j, j]}},
{(k,): {z[k, k]}}
]
}
]
}
assert get_contraction_structure(ii_jj_kk) == expected
def test_ufunc_support():
f = Function('f')
g = Function('g')
x = IndexedBase('x')
y = IndexedBase('y')
i, j = Idx('i'), Idx('j')
a = symbols('a')
assert get_indices(f(x[i])) == ({i}, {})
assert get_indices(f(x[i], y[j])) == ({i, j}, {})
assert get_indices(f(y[i])*g(x[i])) == (set(), {})
assert get_indices(f(a, x[i])) == ({i}, {})
assert get_indices(f(a, y[i], x[j])*g(x[i])) == ({j}, {})
assert get_indices(g(f(x[i]))) == ({i}, {})
assert get_contraction_structure(f(x[i])) == {None: {f(x[i])}}
assert get_contraction_structure(
f(y[i])*g(x[i])) == {(i,): {f(y[i])*g(x[i])}}
assert get_contraction_structure(
f(y[i])*g(f(x[i]))) == {(i,): {f(y[i])*g(f(x[i]))}}
assert get_contraction_structure(
f(x[j], y[i])*g(x[i])) == {(i,): {f(x[j], y[i])*g(x[i])}}