Add MPS and GZ support in translators

.pylintdict

@@ -81,6 +81,7 @@ gurobi
 gurobioptimizer
 gurobipy
 gutmann
+gzip'ed
 hamilton
 hamiltonian
 hamiltonians
@@ -125,6 +126,7 @@ minimizer
 minimumeigenoptimizer
 mmp
 mpm
+mps
 multiset
 mypy
 nannicini
@@ -233,6 +235,7 @@ transpiling
 travelling
 troyer
 tsplib
+uncompress
 undirected
 upperbound
 variational

docs/tutorials/01_quadratic_program.ipynb

@@ -390,7 +390,7 @@
       "\n",
       "quadratic dict w/ index:\t {(0, 1): 2, (2, 2): -1}\n",
       "quadratic dict w/ name:\t\t {('x', 'y'): 2, ('z', 'z'): -1}\n",
-      "symmetric quadratic dict w/ name:\t {('y', 'x'): 1, ('x', 'y'): 1, ('z', 'z'): -1}\n",
+      "symmetric quadratic dict w/ name:\t {('x', 'y'): 1, ('y', 'x'): 1, ('z', 'z'): -1}\n",
       "quadratic matrix:\n",
       " [[ 0  2  0]\n",
       " [ 0  0  0]\n",
@@ -786,12 +786,15 @@
     }
    ],
    "source": [
+    "from qiskit_optimization.translators import export_as_lp_string\n",
+    "\n",
     "mod = QuadraticProgram()\n",
     "mod.binary_var(name=\"e\")\n",
     "mod.binary_var(name=\"f\")\n",
     "mod.continuous_var(name=\"g\")\n",
     "mod.minimize(linear=[1, 2, 3])\n",
-    "print(mod.export_as_lp_string())"
+    "\n",
+    "print(export_as_lp_string(mod))"
    ]
   },
   {
@@ -802,7 +805,7 @@
     {
      "data": {
       "text/html": [
-       "<h3>Version Information</h3><table><tr><th>Qiskit Software</th><th>Version</th></tr><tr><td><code>qiskit-terra</code></td><td>0.21.0.dev0+dbd3961</td></tr><tr><td><code>qiskit-aer</code></td><td>0.10.4</td></tr><tr><td><code>qiskit-ibmq-provider</code></td><td>0.19.1</td></tr><tr><td><code>qiskit-optimization</code></td><td>0.4.0</td></tr><tr><th>System information</th></tr><tr><td>Python version</td><td>3.10.4</td></tr><tr><td>Python compiler</td><td>GCC 11.2.0</td></tr><tr><td>Python build</td><td>main, Apr  2 2022 09:04:19</td></tr><tr><td>OS</td><td>Linux</td></tr><tr><td>CPUs</td><td>4</td></tr><tr><td>Memory (Gb)</td><td>14.577545166015625</td></tr><tr><td colspan='2'>Wed May 18 16:03:27 2022 JST</td></tr></table>"
+       "<h3>Version Information</h3><table><tr><th>Software</th><th>Version</th></tr><tr><td><code>qiskit</code></td><td>0.45.1</td></tr><tr><td><code>qiskit_optimization</code></td><td>0.7.0</td></tr><tr><th colspan='2'>System information</th></tr><tr><td>Python version</td><td>3.10.13</td></tr><tr><td>Python compiler</td><td>GCC 13.2.1 20231205 (Red Hat 13.2.1-6)</td></tr><tr><td>Python build</td><td>main, Dec 18 2023 00:00:00</td></tr><tr><td>OS</td><td>Linux</td></tr><tr><td>CPUs</td><td>12</td></tr><tr><td>Memory (Gb)</td><td>31.056407928466797</td></tr><tr><td colspan='2'>Mon Feb 05 10:25:02 2024 CET</td></tr></table>"
       ],
       "text/plain": [
        "<IPython.core.display.HTML object>"
@@ -814,7 +817,7 @@
     {
      "data": {
       "text/html": [
-       "<div style='width: 100%; background-color:#d5d9e0;padding-left: 10px; padding-bottom: 10px; padding-right: 10px; padding-top: 5px'><h3>This code is a part of Qiskit</h3><p>&copy; Copyright IBM 2017, 2022.</p><p>This code is licensed under the Apache License, Version 2.0. You may<br>obtain a copy of this license in the LICENSE.txt file in the root directory<br> of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.<p>Any modifications or derivative works of this code must retain this<br>copyright notice, and modified files need to carry a notice indicating<br>that they have been altered from the originals.</p></div>"
+       "<div style='width: 100%; background-color:#d5d9e0;padding-left: 10px; padding-bottom: 10px; padding-right: 10px; padding-top: 5px'><h3>This code is a part of Qiskit</h3><p>&copy; Copyright IBM 2017, 2024.</p><p>This code is licensed under the Apache License, Version 2.0. You may<br>obtain a copy of this license in the LICENSE.txt file in the root directory<br> of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.<p>Any modifications or derivative works of this code must retain this<br>copyright notice, and modified files need to carry a notice indicating<br>that they have been altered from the originals.</p></div>"
       ],
       "text/plain": [
        "<IPython.core.display.HTML object>"
@@ -840,8 +843,22 @@
   }
  ],
  "metadata": {
+  "kernelspec": {
+   "display_name": "venv",
+   "language": "python",
+   "name": "python3"
+  },
   "language_info": {
-   "name": "python"
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.10.13"
   }
  },
  "nbformat": 4,

qiskit_optimization/algorithms/admm_optimizer.py

@@ -25,6 +25,7 @@
 from ..problems.linear_expression import LinearExpression
 from ..problems.quadratic_program import QuadraticProgram
 from ..problems.variable import Variable, VarType
+from ..translators import export_as_lp_string
 from .minimum_eigen_optimizer import MinimumEigenOptimizer
 from .optimization_algorithm import (
     OptimizationAlgorithm,
@@ -282,7 +283,7 @@ def solve(self, problem: QuadraticProgram) -> ADMMOptimizationResult:
         self._verify_compatibility(problem)
 
         # debug
-        self._log.debug("Initial problem: %s", problem.export_as_lp_string())
+        self._log.debug("Initial problem: %s", export_as_lp_string(problem))
 
         # map integer variables to binary variables
         from ..converters.integer_to_binary import IntegerToBinary
@@ -321,15 +322,15 @@ def solve(self, problem: QuadraticProgram) -> ADMMOptimizationResult:
                 op1 = self._create_step1_problem()
                 self._state.x0 = self._update_x0(op1)
                 # debug
-                self._log.debug("Step 1 sub-problem: %s", op1.export_as_lp_string())
+                self._log.debug("Step 1 sub-problem: %s", export_as_lp_string(op1))
             # else, no binary variables exist, and no update to be done in this case.
             # debug
             self._log.debug("x0=%s", self._state.x0)
 
             op2 = self._create_step2_problem()
             self._state.u, self._state.z = self._update_x1(op2)
             # debug
-            self._log.debug("Step 2 sub-problem: %s", op2.export_as_lp_string())
+            self._log.debug("Step 2 sub-problem: %s", export_as_lp_string(op2))
             self._log.debug("u=%s", self._state.u)
             self._log.debug("z=%s", self._state.z)
 
@@ -338,7 +339,7 @@ def solve(self, problem: QuadraticProgram) -> ADMMOptimizationResult:
                     op3 = self._create_step3_problem()
                     self._state.y = self._update_y(op3)
                     # debug
-                    self._log.debug("Step 3 sub-problem: %s", op3.export_as_lp_string())
+                    self._log.debug("Step 3 sub-problem: %s", export_as_lp_string(op3))
                 # debug
                 self._log.debug("y=%s", self._state.y)
 

qiskit_optimization/problems/quadratic_program.py

@@ -1,6 +1,6 @@
 # This code is part of a Qiskit project.
 #
-# (C) Copyright IBM 2019, 2023.
+# (C) Copyright IBM 2019, 2024.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -20,8 +20,8 @@
 from warnings import warn
 
 import numpy as np
-from docplex.mp.model_reader import ModelReader
 from numpy import ndarray
+from qiskit.utils.deprecation import deprecate_func
 from qiskit.quantum_info import SparsePauliOp
 from qiskit.quantum_info.operators.base_operator import BaseOperator
 from scipy.sparse import spmatrix
@@ -911,52 +911,58 @@ def _copy_from(self, other: "QuadraticProgram", include_name: bool) -> None:
                         elem.quadratic_program = self
             setattr(self, attr, val)
 
+    @deprecate_func(
+        additional_msg=(
+            "Please use export_as_lp_string from qiskit_optimization.translators.file_io instead."
+        ),
+        since="0.6.0",
+        pending=True,
+    )
     def export_as_lp_string(self) -> str:
         """Returns the quadratic program as a string of LP format.
 
         Returns:
             A string representing the quadratic program.
         """
+
         # pylint: disable=cyclic-import
-        from ..translators.docplex_mp import to_docplex_mp
+        from ..translators.file_io import export_as_lp_string
 
-        return to_docplex_mp(self).export_as_lp_string()
+        return export_as_lp_string(self)
 
     @_optionals.HAS_CPLEX.require_in_call
+    @deprecate_func(
+        additional_msg=(
+            "Please use read_from_lp_file from qiskit_optimization.translators.file_io instead."
+        ),
+        since="0.6.0",
+        pending=True,
+    )
     def read_from_lp_file(self, filename: str) -> None:
-        """Loads the quadratic program from a LP file.
+        """Loads the quadratic program from a LP file (may be gzip'ed).
 
         Args:
             filename: The filename of the file to be loaded.
 
         Raises:
-            FileNotFoundError: If the file does not exist.
+            IOError: If the file type is not recognized, not supported or the file is not found.
 
         Note:
             This method requires CPLEX to be installed and present in ``PYTHONPATH``.
         """
 
-        def _parse_problem_name(filename: str) -> str:
-            # Because docplex model reader uses the base name as model name,
-            # we parse the model name in the LP file manually.
-            # https://ibmdecisionoptimization.github.io/docplex-doc/mp/docplex.mp.model_reader.html
-            prefix = "\\Problem name:"
-            model_name = ""
-            with open(filename, encoding="utf8") as file:
-                for line in file:
-                    if line.startswith(prefix):
-                        model_name = line[len(prefix) :].strip()
-                    if not line.startswith("\\"):
-                        break
-            return model_name
-
         # pylint: disable=cyclic-import
-        from ..translators.docplex_mp import from_docplex_mp
+        from ..translators.file_io import read_from_lp_file
 
-        model = ModelReader().read(filename, model_name=_parse_problem_name(filename))
-        other = from_docplex_mp(model)
-        self._copy_from(other, include_name=True)
+        self._copy_from(read_from_lp_file(filename), include_name=True)
 
+    @deprecate_func(
+        additional_msg=(
+            "Please use write_to_lp_file from qiskit_optimization.translators.file_io instead."
+        ),
+        since="0.6.0",
+        pending=True,
+    )
     def write_to_lp_file(self, filename: str) -> None:
         """Writes the quadratic program to an LP file.
 
@@ -969,11 +975,11 @@ def write_to_lp_file(self, filename: str) -> None:
             OSError: If this cannot open a file.
             DOcplexException: If filename is an empty string
         """
+
         # pylint: disable=cyclic-import
-        from ..translators.docplex_mp import to_docplex_mp
+        from ..translators.file_io import write_to_lp_file
 
-        mdl = to_docplex_mp(self)
-        mdl.export_as_lp(filename)
+        write_to_lp_file(self, filename)
 
     def substitute_variables(
         self,

qiskit_optimization/translators/__init__.py

@@ -34,6 +34,14 @@
 """
 
 from .docplex_mp import from_docplex_mp, to_docplex_mp
+from .file_io import (
+    export_as_lp_string,
+    export_as_mps_string,
+    read_from_lp_file,
+    read_from_mps_file,
+    write_to_lp_file,
+    write_to_mps_file,
+)
 from .gurobipy import from_gurobipy, to_gurobipy
 from .ising import from_ising, to_ising
 
@@ -44,4 +52,10 @@
     "to_gurobipy",
     "from_ising",
     "to_ising",
+    "export_as_lp_string",
+    "export_as_mps_string",
+    "read_from_lp_file",
+    "read_from_mps_file",
+    "write_to_lp_file",
+    "write_to_mps_file",
 ]