Add list primitives from Quartic speedups paper

dev_tools/qualtran_dev_tools/notebook_specs.py

@@ -37,6 +37,7 @@
 import qualtran.bloqs.arithmetic.controlled_add_or_subtract
 import qualtran.bloqs.arithmetic.controlled_addition
 import qualtran.bloqs.arithmetic.conversions
+import qualtran.bloqs.arithmetic.lists
 import qualtran.bloqs.arithmetic.multiplication
 import qualtran.bloqs.arithmetic.negate
 import qualtran.bloqs.arithmetic.permutation
@@ -488,6 +489,15 @@
         module=qualtran.bloqs.arithmetic.trigonometric,
         bloq_specs=[qualtran.bloqs.arithmetic.trigonometric.arcsin._ARCSIN_DOC],
     ),
+    NotebookSpecV2(
+        title='List Functions',
+        module=qualtran.bloqs.arithmetic.lists,
+        bloq_specs=[
+            qualtran.bloqs.arithmetic.lists.sort_in_place._SORT_IN_PLACE_DOC,
+            qualtran.bloqs.arithmetic.lists.symmetric_difference._SYMMETRIC_DIFFERENCE_DOC,
+            qualtran.bloqs.arithmetic.lists.has_duplicates._HAS_DUPLICATES_DOC,
+        ],
+    ),
 ]
 
 MOD_ARITHMETIC = [

docs/bloqs/index.rst

@@ -75,6 +75,7 @@ Bloqs Library
     arithmetic/permutation.ipynb
     arithmetic/bitwise.ipynb
     arithmetic/trigonometric/trigonometric.ipynb
+    arithmetic/lists/lists.ipynb
 
 .. toctree::
     :maxdepth: 2

qualtran/bloqs/arithmetic/lists/__init__.py

@@ -0,0 +1,16 @@
+#  Copyright 2024 Google LLC
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+from .has_duplicates import HasDuplicates
+from .sort_in_place import SortInPlace
+from .symmetric_difference import SymmetricDifference

qualtran/bloqs/arithmetic/lists/has_duplicates.py

@@ -0,0 +1,176 @@
+#  Copyright 2024 Google LLC
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+from collections import Counter
+from typing import Union
+
+import attrs
+import numpy as np
+from attrs import frozen
+
+from qualtran import (
+    AddControlledT,
+    Bloq,
+    bloq_example,
+    BloqBuilder,
+    BloqDocSpec,
+    CtrlSpec,
+    QBit,
+    QInt,
+    QUInt,
+    Register,
+    Signature,
+    Soquet,
+    SoquetT,
+)
+from qualtran.bloqs.arithmetic import LinearDepthHalfLessThan
+from qualtran.bloqs.basic_gates import CNOT, XGate
+from qualtran.bloqs.mcmt import MultiControlX
+from qualtran.resource_counting import BloqCountDictT, SympySymbolAllocator
+from qualtran.simulation.classical_sim import ClassicalValT
+from qualtran.symbolics import HasLength, is_symbolic, SymbolicInt
+
+
+@frozen
+class HasDuplicates(Bloq):
+    r"""Given a sorted list of `l` numbers, check if it contains any duplicates.
+
+    Produces a single qubit which is `1` if there are duplicates, and `0` if all are disjoint.
+    It compares every adjacent pair, and therefore uses `l - 1` comparisons.
+    It then uses a single MCX on `l - 1` bits gate to compute the flag.
+
+    Args:
+        l: number of elements in the list
+        dtype: type of each element to store `[n]`.
+
+    Registers:
+        xs: a list of `l` registers of `dtype`.
+        flag: single qubit. Value is flipped if the input list has duplicates, otherwise stays same.
+
+    References:
+        [Quartic quantum speedups for planted inference](https://arxiv.org/abs/2406.19378v1)
+        Lemma 4.12. Eq. 122.
+    """
+
+    l: SymbolicInt
+    dtype: Union[QUInt, QInt]
+    is_controlled: bool = False
+
+    @property
+    def signature(self) -> 'Signature':
+        registers = [Register('xs', self.dtype, shape=(self.l,)), Register('flag', QBit())]
+        if self.is_controlled:
+            registers.append(Register('ctrl', QBit()))
+        return Signature(registers)
+
+    @property
+    def _le_bloq(self) -> LinearDepthHalfLessThan:
+        return LinearDepthHalfLessThan(self.dtype)
+
+    def build_composite_bloq(
+        self, bb: 'BloqBuilder', xs: 'SoquetT', flag: 'Soquet', **extra_soqs: 'SoquetT'
+    ) -> dict[str, 'SoquetT']:
+        assert not is_symbolic(self.l)
+        assert isinstance(xs, np.ndarray)
+
+        cs = []
+        oks = []
+        if self.is_controlled:
+            oks = [extra_soqs.pop('ctrl')]
+        assert not extra_soqs
+
+        for i in range(1, self.l):
+            xs[i - 1], xs[i], c, ok = bb.add(self._le_bloq, a=xs[i - 1], b=xs[i])
+            cs.append(c)
+            oks.append(ok)
+
+        oks, flag = bb.add(MultiControlX((1,) * len(oks)), controls=np.array(oks), target=flag)
+        if not self.is_controlled:
+            flag = bb.add(XGate(), q=flag)
+        else:
+            oks[0], flag = bb.add(CNOT(), ctrl=oks[0], target=flag)
+
+        oks = list(oks)
+        for i in reversed(range(1, self.l)):
+            xs[i - 1], xs[i] = bb.add(
+                self._le_bloq.adjoint(), a=xs[i - 1], b=xs[i], c=cs.pop(), target=oks.pop()
+            )
+
+        if self.is_controlled:
+            extra_soqs = {'ctrl': oks.pop()}
+        assert not oks
+
+        return {'xs': xs, 'flag': flag} | extra_soqs
+
+    def build_call_graph(self, ssa: 'SympySymbolAllocator') -> BloqCountDictT:
+        counts = Counter[Bloq]()
+
+        counts[self._le_bloq] += self.l - 1
+        counts[self._le_bloq.adjoint()] += self.l - 1
+
+        n_ctrls = self.l - (1 if not self.is_controlled else 0)
+        counts[MultiControlX(HasLength(n_ctrls))] += 1
+
+        counts[XGate() if not self.is_controlled else CNOT()] += 1
+
+        return counts
+
+    def on_classical_vals(self, **vals: 'ClassicalValT') -> dict[str, 'ClassicalValT']:
+        xs = np.asarray(vals['xs'])
+        assert np.all(xs == np.sort(xs))
+        if np.any(xs[:-1] == xs[1:]):
+            vals['flag'] ^= 1
+        return vals
+
+    def adjoint(self) -> 'HasDuplicates':
+        return self
+
+    def get_ctrl_system(self, ctrl_spec: 'CtrlSpec') -> tuple['Bloq', 'AddControlledT']:
+        from qualtran.bloqs.mcmt.specialized_ctrl import get_ctrl_system_1bit_cv_from_bloqs
+
+        return get_ctrl_system_1bit_cv_from_bloqs(
+            self,
+            ctrl_spec,
+            current_ctrl_bit=1 if self.is_controlled else None,
+            bloq_with_ctrl=attrs.evolve(self, is_controlled=True),
+            ctrl_reg_name='ctrl',
+        )
+
+
+@bloq_example
+def _has_duplicates() -> HasDuplicates:
+    has_duplicates = HasDuplicates(4, QUInt(3))
+    return has_duplicates
+
+
+@bloq_example
+def _has_duplicates_symb() -> HasDuplicates:
+    import sympy
+
+    n = sympy.Symbol("n")
+    has_duplicates_symb = HasDuplicates(4, QUInt(n))
+    return has_duplicates_symb
+
+
+@bloq_example
+def _has_duplicates_symb_len() -> HasDuplicates:
+    import sympy
+
+    l, n = sympy.symbols("l n")
+    has_duplicates_symb_len = HasDuplicates(l, QUInt(n))
+    return has_duplicates_symb_len
+
+
+_HAS_DUPLICATES_DOC = BloqDocSpec(
+    bloq_cls=HasDuplicates, examples=[_has_duplicates_symb, _has_duplicates]
+)

qualtran/bloqs/arithmetic/lists/has_duplicates_test.py

@@ -0,0 +1,56 @@
+#  Copyright 2024 Google LLC
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+import itertools
+
+import numpy as np
+import pytest
+
+import qualtran.testing as qlt_testing
+from qualtran import QInt, QUInt
+from qualtran.bloqs.arithmetic.lists.has_duplicates import (
+    _has_duplicates,
+    _has_duplicates_symb,
+    _has_duplicates_symb_len,
+    HasDuplicates,
+)
+
+
+@pytest.mark.parametrize(
+    "bloq_ex",
+    [_has_duplicates, _has_duplicates_symb, _has_duplicates_symb_len],
+    ids=lambda b: b.name,
+)
+def test_examples(bloq_autotester, bloq_ex):
+    bloq_autotester(bloq_ex)
+
+
+@pytest.mark.parametrize("bloq_ex", [_has_duplicates, _has_duplicates_symb], ids=lambda b: b.name)
+def test_counts(bloq_ex):
+    qlt_testing.assert_equivalent_bloq_counts(bloq_ex())
+
+
+@pytest.mark.parametrize("l", [2, 3, pytest.param(4, marks=pytest.mark.slow)])
+@pytest.mark.parametrize(
+    "dtype", [QUInt(2), QInt(2), pytest.param(QUInt(3), marks=pytest.mark.slow)]
+)
+def test_classical_action(l, dtype):
+    bloq = HasDuplicates(l, dtype)
+    cbloq = bloq.decompose_bloq()
+
+    for xs_t in itertools.product(dtype.get_classical_domain(), repeat=l):
+        xs = np.sort(xs_t)
+        for flag in [0, 1]:
+            np.testing.assert_equal(
+                cbloq.call_classically(xs=xs, flag=flag), bloq.call_classically(xs=xs, flag=flag)
+            )