From cd22eb1699c4069cdd1517f34d3e145eff883e0f Mon Sep 17 00:00:00 2001
From: santi <santiago.penate.vera@gmail.com>
Date: Tue, 9 Jan 2024 09:15:05 +0000
Subject: [PATCH] Added the simple mip interface (untested)

---
 .idea/workspace.xml                           | 211 +++---
 requirements.txt                              |   5 +-
 .../Core/Compilers/circuit_to_bentayga.py     |   1 +
 .../Core/Compilers/circuit_to_newton_pa.py    |   1 +
 .../Core/Compilers/circuit_to_optimods.py     |   3 +-
 .../Core/Compilers/circuit_to_pgm.py          |   1 +
 .../Utils/MIP/SimpleMip/__init__.py           |  20 +
 .../Utils/MIP/SimpleMip/highs.py              |  88 +++
 .../Utils/MIP/SimpleMip/lpcst.py              | 101 +++
 .../Utils/MIP/SimpleMip/lpexp.py              | 185 ++++++
 .../Utils/MIP/SimpleMip/lpvar.py              | 129 ++++
 .../Utils/MIP/SimpleMip/problem.py            | 618 ++++++++++++++++++
 .../Utils/MIP/selected_interface.py           |   3 +-
 13 files changed, 1260 insertions(+), 106 deletions(-)
 create mode 100644 src/GridCalEngine/Utils/MIP/SimpleMip/__init__.py
 create mode 100644 src/GridCalEngine/Utils/MIP/SimpleMip/highs.py
 create mode 100644 src/GridCalEngine/Utils/MIP/SimpleMip/lpcst.py
 create mode 100644 src/GridCalEngine/Utils/MIP/SimpleMip/lpexp.py
 create mode 100644 src/GridCalEngine/Utils/MIP/SimpleMip/lpvar.py
 create mode 100644 src/GridCalEngine/Utils/MIP/SimpleMip/problem.py

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index c9df09775..f0ae81bf1 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -28,9 +28,20 @@
     <select />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="aa3ee678-6e91-470f-91a9-09e9d8a4756d" name="Changes" comment="Make copy of fluid node, maybe have to do for all fluid">
+    <list default="true" id="aa3ee678-6e91-470f-91a9-09e9d8a4756d" name="Changes" comment="re-made ding0_test_network_2_mvlv.gridcal with capex&#10;implemented the MVRSM multi-objective">
+      <change afterPath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/SimpleMip/__init__.py" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/SimpleMip/highs.py" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/SimpleMip/lpcst.py" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/SimpleMip/lpexp.py" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/SimpleMip/lpvar.py" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/SimpleMip/problem.py" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/GridCalEngine/Core/Devices/Fluid/fluid_node.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/GridCalEngine/Core/Devices/Fluid/fluid_node.py" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/requirements.txt" beforeDir="false" afterPath="$PROJECT_DIR$/requirements.txt" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_bentayga.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_bentayga.py" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_newton_pa.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_newton_pa.py" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_optimods.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_optimods.py" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_pgm.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/GridCalEngine/Core/Compilers/circuit_to_pgm.py" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/selected_interface.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/GridCalEngine/Utils/MIP/selected_interface.py" afterDir="false" />
     </list>
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     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -116,8 +127,6 @@
     &quot;MATLAB_INTERPRETER&quot;: &quot;/usr/local/MATLAB/R2018a/bin/matlab&quot;,
     &quot;Python tests.Nosetests in acopf_function_evaluation.py.executor&quot;: &quot;Run&quot;,
     &quot;Python.ExecuteGridCal.executor&quot;: &quot;Run&quot;,
-    &quot;Python.acopf_function_evaluation.executor&quot;: &quot;Debug&quot;,
-    &quot;Python.hydro_opf.executor&quot;: &quot;Run&quot;,
     &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
     &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
     &quot;WebServerToolWindowFactoryState&quot;: &quot;false&quot;,
@@ -175,50 +184,6 @@
       <option name="OPTIONS" value="" />
       <method v="2" />
     </configuration>
-    <configuration default="true" type="DjangoTestsConfigurationType">
-      <module name="GridCalEngine" />
-      <option name="ENV_FILES" value="" />
-      <option name="INTERPRETER_OPTIONS" value="" />
-      <option name="PARENT_ENVS" value="true" />
-      <envs>
-        <env name="PYTHONUNBUFFERED" value="1" />
-      </envs>
-      <option name="SDK_HOME" value="" />
-      <option name="WORKING_DIRECTORY" value="" />
-      <option name="IS_MODULE_SDK" value="false" />
-      <option name="ADD_CONTENT_ROOTS" value="true" />
-      <option name="ADD_SOURCE_ROOTS" value="true" />
-      <EXTENSION ID="PythonCoverageRunConfigurationExtension" runner="coverage.py" />
-      <option name="TARGET" value="" />
-      <option name="SETTINGS_FILE" value="" />
-      <option name="CUSTOM_SETTINGS" value="false" />
-      <option name="USE_OPTIONS" value="false" />
-      <option name="OPTIONS" value="" />
-      <method v="2" />
-    </configuration>
-    <configuration default="true" type="MatlabApplication">
-      <option name="FILE_PATH" value="" />
-      <option name="INTERPRETER_PATH" value="" />
-      <option name="WORKING_DIRECTORY" value="" />
-      <option name="PARENT_ENVS" value="true" />
-      <option name="PARAMETERS" value="" />
-      <option name="INTERPRETER_OPTIONS" value="" />
-      <method v="2" />
-    </configuration>
-    <configuration default="true" type="PyBehaveRunConfigurationType" factoryName="Behave">
-      <module name="GridCalEngine" />
-      <option name="ENV_FILES" value="" />
-      <option name="INTERPRETER_OPTIONS" value="" />
-      <option name="PARENT_ENVS" value="true" />
-      <option name="SDK_HOME" value="" />
-      <option name="WORKING_DIRECTORY" value="" />
-      <option name="IS_MODULE_SDK" value="true" />
-      <option name="ADD_CONTENT_ROOTS" value="true" />
-      <option name="ADD_SOURCE_ROOTS" value="true" />
-      <EXTENSION ID="PythonCoverageRunConfigurationExtension" runner="coverage.py" />
-      <option name="ADDITIONAL_ARGS" value="" />
-      <method v="2" />
-    </configuration>
     <configuration default="true" type="PyBehaveRunConfigurationType" factoryName="Behave">
       <module name="GridCalEngine" />
       <option name="ENV_FILES" value="" />
@@ -235,6 +200,7 @@
     </configuration>
     <configuration default="true" type="PythonConfigurationType" factoryName="Python">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <envs>
@@ -269,22 +235,9 @@
       <option name="launchJavascriptDebuger" value="false" />
       <method v="2" />
     </configuration>
-    <configuration default="true" type="Python.FlaskServer">
-      <module name="GridCalEngine" />
-      <option name="ENV_FILES" value="" />
-      <option name="INTERPRETER_OPTIONS" value="" />
-      <option name="PARENT_ENVS" value="true" />
-      <option name="SDK_HOME" value="" />
-      <option name="WORKING_DIRECTORY" value="" />
-      <option name="IS_MODULE_SDK" value="false" />
-      <option name="ADD_CONTENT_ROOTS" value="true" />
-      <option name="ADD_SOURCE_ROOTS" value="true" />
-      <EXTENSION ID="PythonCoverageRunConfigurationExtension" runner="coverage.py" />
-      <option name="launchJavascriptDebuger" value="false" />
-      <method v="2" />
-    </configuration>
     <configuration default="true" type="Tox" factoryName="Tox">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -297,6 +250,7 @@
     </configuration>
     <configuration default="true" type="docs" factoryName="Docutils task">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -314,6 +268,7 @@
     </configuration>
     <configuration default="true" type="docs" factoryName="Sphinx task">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -331,6 +286,7 @@
     </configuration>
     <configuration default="true" type="tests" factoryName="Doctests">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -350,6 +306,7 @@
     </configuration>
     <configuration default="true" type="tests" factoryName="Nosetests">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -366,6 +323,7 @@
     </configuration>
     <configuration default="true" type="tests" factoryName="py.test">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -381,8 +339,53 @@
       <option name="_new_targetType" value="&quot;PATH&quot;" />
       <method v="2" />
     </configuration>
+    <configuration default="true" type="DjangoTestsConfigurationType">
+      <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
+      <option name="INTERPRETER_OPTIONS" value="" />
+      <option name="PARENT_ENVS" value="true" />
+      <envs>
+        <env name="PYTHONUNBUFFERED" value="1" />
+      </envs>
+      <option name="SDK_HOME" value="" />
+      <option name="WORKING_DIRECTORY" value="" />
+      <option name="IS_MODULE_SDK" value="false" />
+      <option name="ADD_CONTENT_ROOTS" value="true" />
+      <option name="ADD_SOURCE_ROOTS" value="true" />
+      <EXTENSION ID="PythonCoverageRunConfigurationExtension" runner="coverage.py" />
+      <option name="TARGET" value="" />
+      <option name="SETTINGS_FILE" value="" />
+      <option name="CUSTOM_SETTINGS" value="false" />
+      <option name="USE_OPTIONS" value="false" />
+      <option name="OPTIONS" value="" />
+      <method v="2" />
+    </configuration>
+    <configuration default="true" type="MatlabApplication">
+      <option name="FILE_PATH" value="" />
+      <option name="INTERPRETER_PATH" value="" />
+      <option name="WORKING_DIRECTORY" value="" />
+      <option name="PARENT_ENVS" value="true" />
+      <option name="PARAMETERS" value="" />
+      <option name="INTERPRETER_OPTIONS" value="" />
+      <method v="2" />
+    </configuration>
+    <configuration default="true" type="PyBehaveRunConfigurationType" factoryName="Behave">
+      <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
+      <option name="INTERPRETER_OPTIONS" value="" />
+      <option name="PARENT_ENVS" value="true" />
+      <option name="SDK_HOME" value="" />
+      <option name="WORKING_DIRECTORY" value="" />
+      <option name="IS_MODULE_SDK" value="true" />
+      <option name="ADD_CONTENT_ROOTS" value="true" />
+      <option name="ADD_SOURCE_ROOTS" value="true" />
+      <EXTENSION ID="PythonCoverageRunConfigurationExtension" runner="coverage.py" />
+      <option name="ADDITIONAL_ARGS" value="" />
+      <method v="2" />
+    </configuration>
     <configuration name="ExecuteGridCal" type="PythonConfigurationType" factoryName="Python" temporary="true" nameIsGenerated="true">
       <module name="GridCal" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <envs>
@@ -405,6 +408,7 @@
     </configuration>
     <configuration default="true" type="PythonConfigurationType" factoryName="Python">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <envs>
@@ -427,6 +431,7 @@
     </configuration>
     <configuration name="acopf_jax" type="PythonConfigurationType" factoryName="Python" temporary="true" nameIsGenerated="true">
       <module name="GridCal" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <envs>
@@ -449,6 +454,7 @@
     </configuration>
     <configuration name="hydro_opf" type="PythonConfigurationType" factoryName="Python" temporary="true" nameIsGenerated="true">
       <module name="GridCal" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <envs>
@@ -469,8 +475,23 @@
       <option name="INPUT_FILE" value="" />
       <method v="2" />
     </configuration>
+    <configuration default="true" type="Python.FlaskServer">
+      <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
+      <option name="INTERPRETER_OPTIONS" value="" />
+      <option name="PARENT_ENVS" value="true" />
+      <option name="SDK_HOME" value="" />
+      <option name="WORKING_DIRECTORY" value="" />
+      <option name="IS_MODULE_SDK" value="false" />
+      <option name="ADD_CONTENT_ROOTS" value="true" />
+      <option name="ADD_SOURCE_ROOTS" value="true" />
+      <EXTENSION ID="PythonCoverageRunConfigurationExtension" runner="coverage.py" />
+      <option name="launchJavascriptDebuger" value="false" />
+      <method v="2" />
+    </configuration>
     <configuration default="true" type="Tox" factoryName="Tox">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -483,6 +504,7 @@
     </configuration>
     <configuration default="true" type="docs" factoryName="Docutils task">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -500,6 +522,7 @@
     </configuration>
     <configuration default="true" type="docs" factoryName="Sphinx task">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -517,6 +540,7 @@
     </configuration>
     <configuration name="Nosetests in mips.py" type="tests" factoryName="Nosetests" temporary="true" nameIsGenerated="true">
       <module name="GridCal" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -533,6 +557,7 @@
     </configuration>
     <configuration name="Nosetests in tests" type="tests" factoryName="Nosetests" temporary="true" nameIsGenerated="true">
       <module name="GridCal" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -549,6 +574,7 @@
     </configuration>
     <configuration default="true" type="tests" factoryName="Doctests">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -568,6 +594,7 @@
     </configuration>
     <configuration default="true" type="tests" factoryName="Nosetests">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -584,6 +611,7 @@
     </configuration>
     <configuration default="true" type="tests" factoryName="py.test">
       <module name="GridCalEngine" />
+      <option name="ENV_FILES" value="" />
       <option name="INTERPRETER_OPTIONS" value="" />
       <option name="PARENT_ENVS" value="true" />
       <option name="SDK_HOME" value="" />
@@ -609,9 +637,9 @@
     <recent_temporary>
       <list>
         <item itemvalue="Python.ExecuteGridCal" />
+        <item itemvalue="Python.hydro_opf" />
         <item itemvalue="Python tests.Nosetests in tests" />
         <item itemvalue="Python tests.Nosetests in mips.py" />
-        <item itemvalue="Python.hydro_opf" />
         <item itemvalue="Python.acopf_jax" />
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-      <workItem from="1704444243529" duration="2046000" />
+      <workItem from="1704786041917" duration="5650000" />
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     <task id="LOCAL-00310" summary="implemented newtonPA time series">
       <created>1656059954202</created>
@@ -1600,7 +1626,7 @@
       <option name="project" value="LOCAL" />
       <updated>1698766404661</updated>
     </task>
-    <option name="localTasksCounter" value="445" />
+    <option name="localTasksCounter" value="443" />
     <servers />
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   <component name="TypeScriptGeneratedFilesManager">
@@ -1633,7 +1659,7 @@
                   <entry key="branch">
                     <value>
                       <list>
-                        <option value="203_Ampliacion_OPF_lineal" />
+                        <option value="devel" />
                       </list>
                     </value>
                   </entry>
@@ -1646,6 +1672,8 @@
     </option>
   </component>
   <component name="VcsManagerConfiguration">
+    <MESSAGE value="improved docs" />
+    <MESSAGE value="added investment grid test" />
     <MESSAGE value="added connectivities for fuels emissions and technologies" />
     <MESSAGE value="added connectivity matrices for fuels emissions and technologies to the multi-circuit" />
     <MESSAGE value="5.0.8&#10;improved NR ability to detect sparse solution errors" />
@@ -1669,9 +1697,7 @@
     <MESSAGE value="Change m3 to hm3 in the levels" />
     <MESSAGE value="Use modify function to test variations" />
     <MESSAGE value="Cosmetic changes" />
-    <MESSAGE value="minimal changes to better unify pulp and ortools interfaces" />
-    <MESSAGE value="Make copy of fluid node, maybe have to do for all fluid" />
-    <option name="LAST_COMMIT_MESSAGE" value="Make copy of fluid node, maybe have to do for all fluid" />
+    <option name="LAST_COMMIT_MESSAGE" value="Cosmetic changes" />
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@@ -2090,38 +2116,21 @@
           <option name="timeStamp" value="1212" />
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-          <line>1102</line>
-          <option name="timeStamp" value="1323" />
+          <url>file://$PROJECT_DIR$/src/GridCal/Gui/Main/SubClasses/base_gui.py</url>
+          <line>17</line>
+          <option name="timeStamp" value="1213" />
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-        <watch expression="dh*2" language="Python" />
-        <watch expression="dh*3" language="Python" />
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+  </component>
+  <component name="com.intellij.coverage.CoverageDataManagerImpl">
+    <SUITE FILE_PATH="coverage/GridCal$Nosetests_for_tests_test_contingency.coverage" NAME="Nosetests for tests.test_contingency Coverage Results" MODIFIED="1704269547065" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/src/tests" />
+    <SUITE FILE_PATH="coverage/GridCal$ExecuteGridCal.coverage" NAME="ExecuteGridCal Coverage Results" MODIFIED="1704400051270" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/src/GridCal" />
+    <SUITE FILE_PATH="coverage/GridCal$acopf_function_evaluation.coverage" NAME="acopf_function_evaluation Coverage Results" MODIFIED="1704724094525" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/examples/trunk/acopf" />
+    <SUITE FILE_PATH="coverage/GridCal$upload_to_pypi.coverage" NAME="upload_to_pypi Coverage Results" MODIFIED="1704384315860" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/src" />
+    <SUITE FILE_PATH="coverage/GridCal$hydro_opf.coverage" NAME="hydro_opf Coverage Results" MODIFIED="1704400043683" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/examples" />
+    <SUITE FILE_PATH="coverage/GridCal$Nosetests_in_tests.coverage" NAME="Nosetests in tests Coverage Results" MODIFIED="1704292017290" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/src/tests" />
+    <SUITE FILE_PATH="coverage/GridCal$Nosetests_in_acopf_function_evaluation_py.coverage" NAME="Nosetests in acopf_function_evaluation.py Coverage Results" MODIFIED="1704358701624" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/examples/trunk/acopf" />
+    <SUITE FILE_PATH="coverage/GridCal$Nosetests_for_tests_test_ptdf.coverage" NAME="Nosetests for tests.test_ptdf Coverage Results" MODIFIED="1704291895608" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$/src/tests" />
   </component>
 </project>
\ No newline at end of file
diff --git a/requirements.txt b/requirements.txt
index 1191cdb42..22d12f750 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@ networkx>=2.1
 pandas>=1.1
 xlwt>=1.3.0
 xlrd>=1.1.0
-ortools>=9.8.0
+# ortools>=9.8.0
 matplotlib>=2.1.1
 qtconsole>=4.3.1
 pyDOE>=0.3.8
@@ -28,4 +28,5 @@ windpowerlib
 pvlib
 hyperopt
 requests
-pytest >= 7.2.0
\ No newline at end of file
+pytest >= 7.2.0
+highspy >= 1.5.3
\ No newline at end of file
diff --git a/src/GridCalEngine/Core/Compilers/circuit_to_bentayga.py b/src/GridCalEngine/Core/Compilers/circuit_to_bentayga.py
index a38e48a4c..e2a8e391e 100644
--- a/src/GridCalEngine/Core/Compilers/circuit_to_bentayga.py
+++ b/src/GridCalEngine/Core/Compilers/circuit_to_bentayga.py
@@ -51,6 +51,7 @@
         BENTAYGA_AVAILABLE = True
 
 except ImportError:
+    btg = None
     BENTAYGA_AVAILABLE = False
 
 # numpy integer type for bentayga's uword
diff --git a/src/GridCalEngine/Core/Compilers/circuit_to_newton_pa.py b/src/GridCalEngine/Core/Compilers/circuit_to_newton_pa.py
index e4e795d66..fc78ab316 100644
--- a/src/GridCalEngine/Core/Compilers/circuit_to_newton_pa.py
+++ b/src/GridCalEngine/Core/Compilers/circuit_to_newton_pa.py
@@ -77,6 +77,7 @@
                           f"instead of {NEWTON_PA_VERSION}")
 
 except ImportError as e:
+    npa = None
     NEWTON_PA_AVAILABLE = False
     NEWTON_PA_VERSION = ''
 
diff --git a/src/GridCalEngine/Core/Compilers/circuit_to_optimods.py b/src/GridCalEngine/Core/Compilers/circuit_to_optimods.py
index f20876751..3dd7d6807 100644
--- a/src/GridCalEngine/Core/Compilers/circuit_to_optimods.py
+++ b/src/GridCalEngine/Core/Compilers/circuit_to_optimods.py
@@ -21,7 +21,8 @@
 import json
 import pandas as pd
 from GridCalEngine.Core.Devices.multi_circuit import MultiCircuit
-from GridCalEngine.basic_structures import Logger, SolverType
+from GridCalEngine.enumerations import SolverType
+from GridCalEngine.basic_structures import Logger
 from GridCalEngine.Simulations.PowerFlow.power_flow_options import PowerFlowOptions
 from GridCalEngine.Simulations.PowerFlow.power_flow_results import PowerFlowResults
 from GridCalEngine.Simulations.PowerFlow.power_flow_ts_results import PowerFlowTimeSeriesResults
diff --git a/src/GridCalEngine/Core/Compilers/circuit_to_pgm.py b/src/GridCalEngine/Core/Compilers/circuit_to_pgm.py
index 14d749cf4..9a3286d58 100644
--- a/src/GridCalEngine/Core/Compilers/circuit_to_pgm.py
+++ b/src/GridCalEngine/Core/Compilers/circuit_to_pgm.py
@@ -43,6 +43,7 @@
 
     PGM_AVAILABLE = True
 except ImportError:
+    pgm = None
     PGM_AVAILABLE = False
 
 '''
diff --git a/src/GridCalEngine/Utils/MIP/SimpleMip/__init__.py b/src/GridCalEngine/Utils/MIP/SimpleMip/__init__.py
new file mode 100644
index 000000000..bcaae6ccf
--- /dev/null
+++ b/src/GridCalEngine/Utils/MIP/SimpleMip/__init__.py
@@ -0,0 +1,20 @@
+# GridCal
+# Copyright (C) 2015 - 2023 Santiago Peñate Vera
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 3 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+from GridCalEngine.Utils.MIP.SimpleMip.lpexp import LpExp
+from GridCalEngine.Utils.MIP.SimpleMip.lpvar import LpVar
+from GridCalEngine.Utils.MIP.SimpleMip.problem import LpModel, get_available_mip_solvers, set_var_bounds
diff --git a/src/GridCalEngine/Utils/MIP/SimpleMip/highs.py b/src/GridCalEngine/Utils/MIP/SimpleMip/highs.py
new file mode 100644
index 000000000..ce75cc949
--- /dev/null
+++ b/src/GridCalEngine/Utils/MIP/SimpleMip/highs.py
@@ -0,0 +1,88 @@
+# GridCal
+# Copyright (C) 2015 - 2023 Santiago Peñate Vera
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 3 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+from __future__ import annotations
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:  # Only imports the below statements during type checking
+    from GridCalEngine.Utils.MIP.SimpleMip.problem import Problem
+
+try:
+    import highspy
+    HIGHS_AVAILABLE = True
+except ImportError:
+    highspy = None
+    HIGHS_AVAILABLE = False
+
+
+def solve_with_highs(mip: Problem, verbose: int = 0):
+    """
+    Solve MIP using Highs via its python interface
+    :param mip: Problem to be solved (results are inserted in-place)
+    :param verbose: print info? for values > 0
+    """
+    if highspy is None:
+        raise Exception("No highspy available, try installing with: pip install highspy")
+
+    # declare the solver
+    h = highspy.highs.Highs()
+
+    # declare the LP problem
+    lp = highspy.highs.HighsLp()
+
+    # set the sense
+    lp.sense_ = highspy.highs.ObjSense.kMinimize if mip.is_minimize() else highspy.highs.ObjSense.kMaximize
+
+    # set the var information
+    lp.col_lower_, lp.col_cost_, lp.col_upper_, is_int_list = mip.get_var_data()
+    lp.offset_ = mip.objective.offset
+
+    for i in is_int_list:
+        lp.integrality_.append(i)
+
+    # set the constraints information
+    lp.row_lower_, A, lp.row_upper_ = mip.get_coefficients_data()
+    lp.num_col_ = A.shape[1]
+    lp.num_row_ = A.shape[0]
+
+    lp.a_matrix_.start_ = A.indptr
+    lp.a_matrix_.index_ = A.indices
+    lp.a_matrix_.value_ = A.data
+
+    # send the model to the solver
+    h.passModel(lp)
+
+    # solve
+    h.run()
+
+    # gather results
+    solution = h.getSolution()
+    basis = h.getBasis()
+    info = h.getInfo()
+    model_status = h.getModelStatus()
+
+    if verbose > 0:
+        print("Model status = ", h.modelStatusToString(model_status))
+        print("Optimal objective = ", info.objective_function_value)
+        print("Iteration count = ", info.simplex_iteration_count)
+        print("Primal solution status = ", h.solutionStatusToString(info.primal_solution_status) )
+
+    mip.set_solution(col_values=solution.col_value,
+                     col_duals=solution.col_dual,
+                     row_values=solution.row_value,
+                     row_duals=solution.row_dual,
+                     fixed_values=info.objective_function_value,
+                     optimal_values=model_status == highspy.highs.HighsModelStatus.kOptimal)
diff --git a/src/GridCalEngine/Utils/MIP/SimpleMip/lpcst.py b/src/GridCalEngine/Utils/MIP/SimpleMip/lpcst.py
new file mode 100644
index 000000000..5fc2cb557
--- /dev/null
+++ b/src/GridCalEngine/Utils/MIP/SimpleMip/lpcst.py
@@ -0,0 +1,101 @@
+# GridCal
+# Copyright (C) 2015 - 2023 Santiago Peñate Vera
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 3 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+from __future__ import annotations
+from typing import Tuple, TYPE_CHECKING
+
+if TYPE_CHECKING:  # Only imports the below statements during type checking
+    from GridCalEngine.Utils.MIP.SimpleMip.lpexp import LpExp
+    from GridCalEngine.Utils.MIP.SimpleMip.lpvar import LpVar
+
+
+class LpCst:
+    """
+    Constraint
+    """
+    def __init__(self, linear_expression: LpExp, sense: str, coefficient: float,
+                 name="", internal_index: int = 0):
+        """
+        constraint (<=, ==, >=) rhs
+
+        :param linear_expression:
+        :param sense: <=, ==, >=
+        :param coefficient:
+        :param name:
+        :param internal_index:
+        """
+        assert sense in ["<=", "==", ">="]
+
+        self.name = name
+        self.linear_expression = linear_expression
+        self.sense = sense
+        self.coefficient = coefficient  # Right-hand side value
+        self._index: int = internal_index  # internal index to the solver
+
+    def copy(self) -> "LpCst":
+        """
+        Make a deep copy of this constraint
+        :return: Constraint
+        """
+        return LpCst(linear_expression=self.linear_expression.copy(),
+                     sense=self.sense,
+                     coefficient=self.coefficient,
+                     name=self.name,
+                     internal_index=self._index)
+
+    def get_bounds(self) -> Tuple[float, float]:
+        """
+        Get the constraint bounds
+        :return: lhs <= constraint <= rhs
+        """
+        MIP_INF = 1e20
+        if self.sense == '==':
+            return self.coefficient, self.coefficient
+        elif self.sense == '<=':
+            return -MIP_INF, self.coefficient
+        elif self.sense == '>=':
+            return self.coefficient, MIP_INF
+        else:
+            raise Exception(f"Invalid sense: {self.sense}")
+
+    def set_index(self, index: int) -> None:
+        """
+        Set the internal indexing
+        :param index: constraint index in the solver
+        """
+        self._index = index
+
+    def get_index(self) -> int:
+        """
+        Get internal index
+        :return: int
+        """
+        return self._index
+
+    def add_term(self, var: LpVar, coeff: float):
+        """
+        Add a term to the constraint
+        :param var: Variable
+        :param coeff: coefficient
+        """
+        self.linear_expression += coeff * var
+
+    def add_var(self, var: LpVar):
+        """
+        Add a term to the constraint
+        :param var: Variable
+        """
+        self.linear_expression += var
\ No newline at end of file
diff --git a/src/GridCalEngine/Utils/MIP/SimpleMip/lpexp.py b/src/GridCalEngine/Utils/MIP/SimpleMip/lpexp.py
new file mode 100644
index 000000000..fca69960f
--- /dev/null
+++ b/src/GridCalEngine/Utils/MIP/SimpleMip/lpexp.py
@@ -0,0 +1,185 @@
+# GridCal
+# Copyright (C) 2015 - 2023 Santiago Peñate Vera
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 3 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+from __future__ import annotations
+from typing import Dict, TYPE_CHECKING
+
+if TYPE_CHECKING:  # Only imports the below statements during type checking
+    from GridCalEngine.Utils.MIP.SimpleMip.lpvar import LpVar
+    from GridCalEngine.Utils.MIP.SimpleMip.lpcst import LpCst
+
+
+class LpExp:
+    """
+    Expression
+    """
+    def __init__(self, variable: LpVar = None, coefficient: float = 1.0, offset: float = 0.0):
+        """
+
+        :param variable:
+        :param coefficient:
+        """
+        self.terms: Dict[LpVar, float] = {}
+
+        self.offset = offset
+
+        if variable is not None:
+            self.terms[variable] = coefficient
+
+    def copy(self) -> "LpExp":
+        """
+        Make a deep copy of this expression
+        :return: Expression
+        """
+        e = LpExp()
+
+        for var, coefficient in self.terms.items():
+            e.terms[var.copy()] = coefficient
+
+        e.offset = self.offset
+
+        return e
+
+    def __le__(self, other):
+        sense = "<="
+
+        if isinstance(other, (int, float)):
+            return LpCst(linear_expression=self,
+                         sense=sense,
+                         coefficient=other - self.offset)
+
+        elif isinstance(other, LpVar):
+            other = LpExp(variable=other)
+            combined_expression = self - other
+            return LpCst(combined_expression, sense, 0)
+
+        elif isinstance(other, LpExp):
+            combined_expression = self - other
+            return LpCst(linear_expression=combined_expression,
+                         sense=sense,
+                         coefficient=-combined_expression.offset)
+
+        raise ValueError(f"Right-hand side of {sense} must be an int or float")
+
+    def __ge__(self, other):
+
+        sense = ">="
+
+        if isinstance(other, (int, float)):
+            return LpCst(linear_expression=self,
+                         sense=sense,
+                         coefficient=other - self.offset)
+
+        elif isinstance(other, LpVar):
+            other = LpExp(variable=other)
+            combined_expression = self - other
+            return LpCst(combined_expression, sense, 0)
+
+        elif isinstance(other, LpExp):
+            combined_expression = self - other
+            return LpCst(linear_expression=combined_expression,
+                         sense=sense,
+                         coefficient=-combined_expression.offset)
+
+        raise ValueError(f"Right-hand side of {sense} must be an int or float")
+
+    def __eq__(self, other):
+        sense = "=="
+
+        if isinstance(other, (int, float)):
+            return LpCst(linear_expression=self,
+                         sense=sense,
+                         coefficient=other - self.offset)
+
+        elif isinstance(other, LpVar):
+            other = LpExp(variable=other)
+            combined_expression = self - other
+            return LpCst(combined_expression, sense, 0)
+
+        elif isinstance(other, LpExp):
+            combined_expression = self - other
+            return LpCst(linear_expression=combined_expression,
+                         sense=sense,
+                         coefficient=-combined_expression.offset)
+
+        raise ValueError(f"Right-hand side of {sense} must be an int or float")
+
+    def __add__(self, other):
+        new_expr = LpExp()
+        new_expr.terms = self.terms.copy()
+
+        if isinstance(other, LpVar):
+            other = LpExp(other)
+
+        if isinstance(other, LpExp):
+
+            new_expr.offset += other.offset
+            for var, coeff in other.terms.items():
+                if var in new_expr.terms:
+                    new_expr.terms[var] += coeff
+                else:
+                    new_expr.terms[var] = coeff
+
+        elif isinstance(other, (int, float)):  # Handling constants in expressions
+            new_expr.offset += other
+
+        else:
+            raise ValueError("Operands must be of type Variable, Expression, int, or float")
+
+        return new_expr
+
+    def __radd__(self, other):
+        return self.__add__(other)
+
+    def __mul__(self, other):
+
+        if isinstance(other, (int, float)):
+            new_expr = LpExp()
+            new_expr.offset *= other
+            for var, coeff in self.terms.items():
+                new_expr.terms[var] = coeff * other
+            return new_expr
+
+        else:
+            raise ValueError("Can only multiply by a scalar")
+
+    def __rmul__(self, other):
+        return self.__mul__(other)
+
+    def __sub__(self, other):
+        if isinstance(other, LpVar):
+            other = LpExp(variable=other)
+
+        if isinstance(other, LpExp):
+            new_expr = self.copy()
+            new_expr.offset -= other.offset
+            for var, coeff in other.terms.items():
+                if var in new_expr.terms:
+                    new_expr.terms[var] -= coeff
+                else:
+                    new_expr.terms[var] = -coeff
+            return new_expr
+
+        elif isinstance(other, (int, float)):
+            new_expr = self.copy()
+            new_expr.offset -= other
+            return new_expr
+
+        else:
+            raise ValueError("Unsupported operand type(s) for -: 'Expression' and '{}'".format(type(other)))
+
+    def __rsub__(self, other):
+        return (-1 * self).__add__(other)
diff --git a/src/GridCalEngine/Utils/MIP/SimpleMip/lpvar.py b/src/GridCalEngine/Utils/MIP/SimpleMip/lpvar.py
new file mode 100644
index 000000000..59c6df218
--- /dev/null
+++ b/src/GridCalEngine/Utils/MIP/SimpleMip/lpvar.py
@@ -0,0 +1,129 @@
+# GridCal
+# Copyright (C) 2015 - 2023 Santiago Peñate Vera
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 3 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+from __future__ import annotations
+from typing import Union, TYPE_CHECKING
+from uuid import uuid4
+
+if TYPE_CHECKING:  # Only imports the below statements during type checking
+    from GridCalEngine.Utils.MIP.SimpleMip.lpexp import LpExp
+
+
+class LpVar:
+    """
+    Variable
+    """
+    def __init__(self,
+                 name: str,
+                 lower_bound: float = 0.0,
+                 upper_bound: float = 1e20,
+                 is_integer: bool = False,
+                 internal_idx: int = 0,
+                 hash_id: Union[int, None] = None):
+        """
+
+        :param name: Variable name
+        :param lower_bound: Lower bound (optional)
+        :param upper_bound: Upper bound (optional)
+        :param is_integer: is this an integer variable?  (optional)
+        :param internal_idx: Internal solver index (not required)
+        :param hash_id: internal unique Hash id so that this var can be used in a dictionary as key  (not required)
+        """
+        self.name = name
+        self.lower_bound = lower_bound
+        self.upper_bound = upper_bound
+        self.is_integer = is_integer  # Indicates if the variable is an integer
+        self._index: int = internal_idx  # internal index to the solver
+        self._hash_id: int = uuid4().int if hash_id is None else hash_id
+
+    def set_index(self, index: int) -> None:
+        """
+        Set the internal indexing
+        :param index: var index in the solver
+        """
+        self._index = index
+
+    def get_index(self) -> int:
+        """
+        Get the internal indexing
+        :return: int
+        """
+        return self._index
+
+    def copy(self) -> "LpVar":
+        """
+        Make a deep copy of this variable
+        :return:
+        """
+        return LpVar(name=self.name,
+                     lower_bound=self.lower_bound,
+                     upper_bound=self.upper_bound,
+                     is_integer=self.is_integer,
+                     internal_idx=self._index,
+                     hash_id=self._hash_id)
+
+    def __hash__(self):
+        # Makes Variable instances hashable so they can be used as dictionary keys
+        return self._hash_id
+
+    def __eq__(self, other):
+        # Ensure that variables with the same name are considered equal
+        return isinstance(other, LpVar) and self.name == other.name
+
+    def __add__(self, other):
+        return LpExp(self) + other
+
+    def __radd__(self, other):
+        return LpExp(self) + other
+
+    def __mul__(self, other: Union[int, float]) -> "LpExp":
+        """
+        Multiply this variable with a int or float
+        :param other:
+        :return:
+        """
+        if isinstance(other, (int, float)):
+            return LpExp(self, other)
+        raise ValueError("Can only multiply a Variable by a scalar")
+
+    def __rmul__(self, other):
+        return self.__mul__(other)
+
+    def __sub__(self, other: Union[int, float, "LpVar", "LpExp"]) -> "LpExp":
+        """
+
+        :param other:
+        :return:
+        """
+        if isinstance(other, LpVar):
+            return LpExp(self) - LpExp(other)
+        elif isinstance(other, LpExp):
+            return LpExp(self) - other
+        elif isinstance(other, (int, float)):
+            return LpExp(self) - LpExp(None, other)
+        else:
+            raise ValueError("Unsupported operand type(s) for -: 'Variable' and '{}'".format(type(other)))
+
+    def __rsub__(self, other: Union[int, float]):
+        """
+
+        :param other:
+        :return:
+        """
+        if isinstance(other, (int, float)):
+            return LpExp(None, other) - LpExp(self)
+        else:
+            raise ValueError("Unsupported operand type(s) for -: '{}' and 'Variable'".format(type(other)))
\ No newline at end of file
diff --git a/src/GridCalEngine/Utils/MIP/SimpleMip/problem.py b/src/GridCalEngine/Utils/MIP/SimpleMip/problem.py
new file mode 100644
index 000000000..0436be5cf
--- /dev/null
+++ b/src/GridCalEngine/Utils/MIP/SimpleMip/problem.py
@@ -0,0 +1,618 @@
+# GridCal
+# Copyright (C) 2015 - 2023 Santiago Peñate Vera
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 3 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+from typing import List, Union, Tuple, Iterable
+import numpy as np
+
+from scipy.sparse import csc_matrix
+from GridCalEngine.Utils.MIP.SimpleMip.lpexp import LpExp
+from GridCalEngine.Utils.MIP.SimpleMip.lpcst import LpCst
+from GridCalEngine.Utils.MIP.SimpleMip.lpvar import LpVar
+from GridCalEngine.Utils.MIP.SimpleMip.highs import HIGHS_AVAILABLE, solve_with_highs
+from GridCalEngine.basic_structures import Vec, Logger
+from GridCalEngine.enumerations import MIPSolvers
+
+
+def get_available_mip_solvers() -> List[str]:
+    """
+    Get a list of candidate solvers
+    :return: list of solver names
+    """
+    res = list()
+
+    if HIGHS_AVAILABLE:
+        res.append('HIGHS')
+
+    return res
+
+
+def set_var_bounds(var: LpVar, lb: float, ub: float):
+    """
+    Modify the bounds of a variable
+    :param var: LpVar instance to modify
+    :param lb: lower bound value
+    :param ub: upper bound value
+    """
+    var.lower_bound = lb
+    var.upper_bound = ub
+
+
+class LpModel:
+    """
+    SimpleMIP
+    """
+    OPTIMAL = False
+    INFINITY = 1e20
+    originally_infesible = False
+
+    def __init__(self, solver_type: MIPSolvers = MIPSolvers.HIGHS):
+
+        if solver_type not in [MIPSolvers.HIGHS]:
+            raise Exception(f"Unsupported solver {solver_type.value}")
+
+        self.solver_type = solver_type
+        self.objective: Union[LpExp, None] = None
+        self.constraints: List[LpCst] = []
+        self.variables: List[LpVar] = []
+        self.relaxed_slacks: List[Tuple[int, LpVar, float]] = []
+        self._minimize = True
+        self._is_mip = False
+
+        # solution vars
+        self._col_value = np.empty(0)
+        self._col_dual = np.empty(0)
+        self._row_value = np.empty(0)
+        self._row_dual = np.empty(0)
+        self._objective_value = 0.0
+        self._is_optimal = False
+
+        self.logger = Logger()
+
+    def is_minimize(self) -> bool:
+        """
+        Minimize?
+        :return: bool
+        """
+        return self._minimize
+
+    def copy(self, copy_results: bool = False) -> "LpModel":
+        """
+        Deep copy of this
+        :param copy_results: copy the results too?
+        :return: LpModel
+        """
+        cpy = LpModel(self.solver_type)
+
+        cpy._minimize = self._minimize
+        cpy._is_mip = self._is_mip
+        cpy.objective = self.objective.copy()
+
+        for var in self.variables:
+            cpy.variables.append(var.copy())
+
+        for cst in self.constraints:
+            cpy.constraints.append(cst.copy())
+
+        if copy_results:
+            cpy._col_value = self._col_value
+            cpy._col_dual = self._col_dual
+            cpy._row_value = self._row_value
+            cpy._row_dual = self._row_dual
+            cpy._objective_value = self._objective_value
+            cpy._is_optimal = self._is_optimal
+
+        return cpy
+
+    def get_obj_coefficient(self, var: LpVar) -> float:
+        """
+        Get the coefficient of a variable, if not found, return 0.0
+        """
+        return self.objective.terms.get(var, 0.0)
+
+    def add_variable(self, lb: float = 0.0, ub: float = 1e20, name: str = "", is_int: bool = False):
+        """
+        Add a variable to the problem
+        :param lb:
+        :param ub:
+        :param name:
+        :param is_int:
+        :return: Variable instance
+        """
+        var = LpVar(name=name, lower_bound=lb, upper_bound=ub, is_integer=is_int)
+        self.variables.append(var)
+        return var
+
+    def add_int(self, lb: int, ub: int, name: str = "") -> LpVar:
+        """
+        Make integer LP var
+        :param lb: lower bound
+        :param ub: upper bound
+        :param name: name (optional)
+        :return: LpVar
+        """
+        return self.add_variable(lb=lb, ub=ub, name=name, is_int=True)
+
+    def add_var(self, lb: float, ub: float, name: str = "") -> LpVar:
+        """
+        Make floating point LP var
+        :param lb: lower bound
+        :param ub: upper bound
+        :param name: name (optional)
+        :return: LpVar
+        """
+        return self.add_variable(lb=lb, ub=ub, name=name, is_int=False)
+
+    def _set_objective(self, expression: LpExp, minimize=True):
+        """
+        Set the objective function
+        :param expression: Expression
+        :param minimize: minimize?
+        """
+        self.objective = expression
+        self._minimize = minimize
+
+    def minimize(self, obj_function: LpExp):
+        """
+        Set the objective to minimize
+        :param obj_function: Expression
+        """
+        self._set_objective(obj_function, minimize=True)
+
+    def maximize(self, obj_function: LpExp):
+        """
+        Set the objective to maximize
+        :param obj_function: Expression
+        """
+        self._set_objective(obj_function, minimize=False)
+
+    def add_cst(self, cst: Union[LpCst, bool], name: str = "") -> Union[LpCst, int]:
+        """
+        Add constraint to the model
+        :param cst: constraint object (or general expression)
+        :param name: name of the constraint (optional)
+        :return: Constraint object
+        """
+        if isinstance(cst, bool):
+            return 0
+        elif isinstance(cst, LpCst):
+            cst.name = name
+            self.constraints.append(cst)
+            return cst
+        else:
+            raise ValueError("Only Constraint instances can be added.")
+
+    @staticmethod
+    def sum(expr: Union[LpExp, Iterable]) -> LpExp:
+        """
+        create sum of the expression
+        :param expr: LpExp object (or general expression)
+        :return: LpExp object
+        """
+        if isinstance(expr, LpExp):
+            return expr
+        elif isinstance(expr, Iterable):
+            res = LpExp()
+            for elm in expr:
+                res += elm
+            return res
+        else:
+            raise ValueError("Only iterables can be used with sum.")
+
+    def save_model_to_lp(self, filename: str):
+        """
+        Save model to LP file
+        :param filename: LP file path
+        """
+        with open(filename, 'w') as file:
+            # Write Objective Function
+            obj_type = "Minimize" if self._minimize else "Maximize"
+            objective_expression = " + ".join([f"{coeff}*{var.name}"
+                                               for var, coeff
+                                               in self.objective.terms.items()])
+
+            if self.objective.offset != 0.0:  # Add constant term if exists
+                objective_expression += f" + {self.objective.offset}"
+            file.write(f"{obj_type}\n obj: {objective_expression}\n")
+
+            # Write Constraints
+            file.write("\nSubject To\n")
+            for i, constraint in enumerate(self.constraints):
+                expression = constraint.linear_expression
+                constraint_expression = " + ".join([f"{coeff}*{var.name}"
+                                                    for var, coeff
+                                                    in expression.terms.items()])
+
+                if expression.offset != 0.0:  # Add constant term if exists
+                    objective_expression += f" + {expression.offset}"
+
+                file.write(f" c{i}: {constraint_expression} {constraint.sense} {constraint.coefficient}\n")
+
+            # Write Bounds
+            file.write("\nBounds\n")
+            for var in self.variables:
+                lb = var.lower_bound if var.lower_bound is not None else "-inf"
+                ub = var.upper_bound if var.upper_bound is not None else "inf"
+                file.write(f" {lb} <= {var.name} <= {ub}\n")
+
+            # Write Variable Types
+            file.write("\nGenerals\n")
+            for var in self.variables:
+                if var.is_integer:
+                    file.write(f" {var.name}\n")
+            file.write("End\n")
+
+    def save_model_to_mps(self, filename):
+        """
+        Save the model to MPS
+        :param filename: MPS file path
+        """
+        with open(filename, 'w') as file:
+            # Write the header
+            file.write("NAME          MIPMODEL\n")
+
+            # Write the ROWS section
+            file.write("ROWS\n")
+            file.write(" N  COST\n")
+            for i in range(len(self.constraints)):
+                sense = self.constraints[i].sense
+                if sense == '<=':
+                    file.write(f" L  C{i}\n")
+                elif sense == '>=':
+                    file.write(f" G  C{i}\n")
+                elif sense == '==':
+                    file.write(f" E  C{i}\n")
+
+            # Write the COLUMNS section
+            file.write("COLUMNS\n")
+            for var in self.variables:
+                file.write(f"    {var.name}    COST    {self.objective.terms.get(var, 0)}\n")
+                for i, constraint in enumerate(self.constraints):
+                    coeff = constraint.linear_expression.terms.get(var, 0)
+                    if coeff != 0:
+                        file.write(f"    {var.name}    C{i}    {coeff}\n")
+
+            # Write the RHS section
+            file.write("RHS\n")
+            for i, constraint in enumerate(self.constraints):
+                file.write(f"    RHS1    C{i}    {constraint.coefficient}\n")
+
+            # Write the BOUNDS section
+            file.write("BOUNDS\n")
+            for var in self.variables:
+                lb = var.lower_bound
+                ub = var.upper_bound
+                if var.is_integer:
+                    file.write(f" UI BND1    {var.name}    {ub}\n")
+                    file.write(f" LI BND1    {var.name}    {lb}\n")
+                else:
+                    file.write(f" UP BND1    {var.name}    {ub}\n")
+                    file.write(f" LO BND1    {var.name}    {lb}\n")
+
+            # Optionally add the RANGES section
+            # ...
+
+            # Write the ENDATA section
+            file.write("ENDATA\n")
+
+    def save_model(self, file_name="ntc_opf_problem.lp"):
+        """
+        Save model in lp or mps format
+        :param file_name: name of the file
+        """
+        if file_name.endswith(".lp"):
+            self.save_model_to_lp(filename=file_name)
+
+        elif file_name.endswith(".mps"):
+            self.save_model_to_lp(filename=file_name)
+
+        else:
+            raise Exception(f"Unrecognized file format to save {file_name}")
+
+    def __str__(self):
+        """
+        Formulate MIP
+        :return:
+        """
+        res = ""
+        res += "\nVars:\n"
+        for var in self.variables:
+            var_type = "Integer" if var.is_integer else "Continuous"
+            res += f"{var.name}: {var_type}\n"
+
+        res += "\nObjective:\n"
+        obj_type = "Minimize" if self._minimize else "Maximize"
+
+        objective_expression = " + ".join([f"{coeff} * {var.name}"
+                                           for var, coeff
+                                           in self.objective.terms.items()])
+
+        if self.objective.offset != 0.0:  # Add constant term if exists
+            objective_expression += f" + {self.objective.offset}"
+
+        res += f"{obj_type}: {objective_expression}\n"
+
+        res += "\nConstraints:\n"
+        for i, constraint in enumerate(self.constraints):
+            # Create the constraint expression
+            expression = constraint.linear_expression
+            constraint_expression = " + ".join([f"{coeff}*{var.name}"
+                                                for var, coeff
+                                                in expression.terms.items()])
+
+            if expression.offset != 0.0:  # Add constant term if exists
+                constraint_expression += f" + {expression.offset}"
+
+            res += f"Constraint {i}: {constraint_expression} {constraint.sense} {constraint.coefficient}\n"
+
+        res += "\nBounds:\n"
+        for var in self.variables:
+            bounds = f"{var.lower_bound} <= {var.name} <= {var.upper_bound}"
+            res += bounds + "\n"
+
+        return res
+
+    def get_coefficients_data(self) -> Tuple[np.ndarray, csc_matrix, np.ndarray]:
+        """
+        Returns the coefficients matrix
+        :return:
+        """
+
+        # Initialize lists to hold the row indices, column indices, and data for the A matrix
+        row_indices = []
+        col_indices = []
+        data = []
+
+        n = len(self.constraints)
+        lower = np.empty(n)
+        upper = np.empty(n)
+
+        # Iterate through each constraint, populating the lists
+        for i, constraint in enumerate(self.constraints):
+
+            lower[i], upper[i] = constraint.get_bounds()
+            constraint.set_index(i)
+
+            for var, coeff in constraint.linear_expression.terms.items():
+                if var is not None:  # Skip if it's the constant term
+                    # Row index is the constraint number
+                    row_indices.append(i)
+
+                    # Column index is the variable's index
+                    col_indices.append(self.variables.index(var))
+
+                    # Coefficient is the data
+                    data.append(coeff)
+
+        # Create the A matrix in CSC format
+        A_csc = csc_matrix((data, (row_indices, col_indices)),
+                           shape=(len(self.constraints), len(self.variables)))
+
+        return lower, A_csc, upper
+
+    def get_var_data(self) -> Tuple[Vec, Vec, Vec, List[int]]:
+        """
+        Get arrays related to the variable bounds and the objective function coefficients
+        :return: lower bounds, f obj coefficients, upper bounds, list of integer vars' indices
+        """
+        n = len(self.variables)
+        lower = np.empty(n)
+        coeff = np.empty(n)
+        upper = np.empty(n)
+        is_int = list()
+
+        for i, var in enumerate(self.variables):
+            lower[i] = var.lower_bound
+            coeff[i] = self.get_obj_coefficient(var)
+            upper[i] = var.upper_bound
+            var.set_index(i)
+            if var.is_integer:
+                is_int.append(i)
+
+        return lower, coeff, upper, is_int
+
+    def is_optimal(self) -> bool:
+        """
+
+        :return:
+        """
+        return self._is_optimal
+
+    def _solve(self, model: "LpModel"):
+
+        if self.solver_type == MIPSolvers.HIGHS:
+            solve_with_highs(model)
+
+        else:
+            raise Exception(f"Unsupported solver {self.solver_type.value}")
+
+    def solve(self, robust=True) -> int:
+        """
+        Solve the model
+        :param robust: Relax the problem if infeasible
+        :return: integer value matching OPTIMAL or not
+        """
+
+        self._solve(model=self)
+
+        if not self.is_optimal():
+
+            self.originally_infesible = True
+
+            if robust:
+                """
+                We are going to create a deep clone of the model,
+                add a slack variable to each constraint and minimize
+                the sum of the newly added slack vars.
+                This LP model will be always optimal.
+                After the solution, we inspect the slack vars added
+                if any of those is > 0, then the constraint where it
+                was added needs "slacking", therefore we add that slack
+                to the original model, and add the slack to the original 
+                objective function. This way we relax the model while
+                bringing it to optimality.
+                """
+
+                # deep copy of the original model
+                debug_model = self.copy()
+
+                # modify the original to detect the bad constraints
+                slacks = list()
+                debugging_f_obj = LpExp()
+                for i, cst in enumerate(debug_model.constraints):
+
+                    # create a new slack var in the problem
+                    sl = debug_model.add_var(0, 1e20, name='Slackkk{}'.format(i))
+
+                    # add the variable to the new objective function
+                    debugging_f_obj += sl
+
+                    # add the variable to the current constraint
+                    cst.add_var(sl)
+
+                    # store for later
+                    slacks.append(sl)
+
+                # set the objective function as the summation of the new slacks
+                debug_model.minimize(debugging_f_obj)
+
+                # solve the debug model
+                self._solve(debug_model)
+
+                debug_optimal = debug_model.is_optimal()
+
+                # clear the relaxed slacks list
+                self.relaxed_slacks: List[Tuple[int, LpVar, float]] = []
+
+                if debug_optimal:
+
+                    # pick the original objectve function
+                    main_f = self.objective
+
+                    for i, sl in enumerate(slacks):
+
+                        # get the debugging slack value
+                        val = debug_model.get_value(sl)
+
+                        if val > 1e-10:
+
+                            # add the slack in the main model
+                            sl2 = self.add_var(0, 1e20, name='Slackkk{}'.format(i))
+                            self.relaxed_slacks.append((i, sl2, 0.0))  # the 0.0 value will be read later
+
+                            # add the slack to the original objective function
+                            main_f += sl2
+
+                            # alter the matching constraint
+                            self.constraints[i].add_var(sl2)
+
+                            # logg this
+                            # self.logger.add_warning("Relaxed problem",
+                            #                         device=self.model.linear_constraint_from_index(i).name)
+
+                    # set the modified (original) objective function
+                    self.minimize(main_f)
+
+                    # solve the modified (original) model
+                    self._solve(self)
+
+                    if self.is_optimal():
+
+                        for i in range(len(self.relaxed_slacks)):
+                            k, var, _ = self.relaxed_slacks[i]
+                            val = self.get_value(var)
+                            self.relaxed_slacks[i] = (k, var, val)
+
+                            # logg this
+                            self.logger.add_warning("Relaxed problem",
+                                                    device=self.constraints[i].name,
+                                                    value=val)
+
+                else:
+                    self.logger.add_warning("Unable to relax the model, the debug model failed")
+
+            else:
+                pass
+
+        return 0
+
+    def set_solution(self, col_values: Vec, col_duals: Vec,
+                     row_values: Vec, row_duals: Vec,
+                     f_obj: float, optimal: bool):
+        """
+        Set solution from the MIP solver
+        :param col_values: array of variables' values
+        :param col_duals: array of variable dual values
+        :param row_values: array of constraint values
+        :param row_duals: array of constraint dual values
+        :param f_obj: value of the objective function
+        :param optimal: is optimal
+        """
+        self._col_value = col_values
+        self._col_dual = col_duals
+        self._row_value = row_values
+        self._row_dual = row_duals
+        self._objective_value = f_obj
+        self._is_optimal = optimal
+
+    def fobj_value(self) -> float:
+        """
+        Get the objective function value
+        :return:
+        """
+        return self._objective_value
+
+    def is_mip(self):
+        """
+        Is this model a MIP?
+        :return:
+        """
+
+        return self._is_mip
+
+    def get_value(self, var: LpVar) -> float:
+        """
+        Get the value of a variable
+        :param var: LpVar object
+        :return: float
+        """
+        return self._col_value[var.get_index()]
+
+    def get_dual_value(self, var: LpVar) -> float:
+        """
+        Get the dual value of a variable
+        :param var: LpVar object
+        :return: float
+        """
+        return self._col_dual[var.get_index()]
+
+    def solution_available(self) -> bool:
+        """
+        Is there a solution loaded?
+        :return: true / false
+        """
+        return len(self._col_value) == len(self.variables)
+
+    def print_solution(self):
+        """
+        Print available solution
+        """
+        if self.solution_available():
+            print("Solution")
+            for var in self.variables:
+                print(f"{var.name}: {self._col_value[var.get_index()]}")
+        else:
+            print("No solution available, solve first")
diff --git a/src/GridCalEngine/Utils/MIP/selected_interface.py b/src/GridCalEngine/Utils/MIP/selected_interface.py
index eaa76a174..16dae1860 100644
--- a/src/GridCalEngine/Utils/MIP/selected_interface.py
+++ b/src/GridCalEngine/Utils/MIP/selected_interface.py
@@ -23,9 +23,8 @@
 from scipy.sparse import csc_matrix
 from GridCalEngine.basic_structures import ObjVec, ObjMat, Vec
 
+# from GridCalEngine.Utils.MIP.SimpleMip import LpExp, LpVar, LpModel, get_available_mip_solvers, set_var_bounds
 # from GridCalEngine.Utils.MIP.ortools_interface import LpExp, LpVar, LpModel, get_available_mip_solvers, set_var_bounds
-
-
 from GridCalEngine.Utils.MIP.pulp_interface import LpExp, LpVar, LpModel, get_available_mip_solvers, set_var_bounds