dance858 · dance858 · Mar 2, 2026 · Mar 2, 2026 · Mar 2, 2026 · Mar 2, 2026
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -3,7 +3,7 @@ project(PSLP LANGUAGES C CXX) # The library is written in C, but we also have so
 
 set(PSLP_VERSION_MAJOR 0)
 set(PSLP_VERSION_MINOR 0)
-set(PSLP_VERSION_PATCH 6)
+set(PSLP_VERSION_PATCH 7)
 set(PSLP_VERSION "${PSLP_VERSION_MAJOR}.${PSLP_VERSION_MINOR}.${PSLP_VERSION_PATCH}")
 add_compile_definitions(PSLP_VERSION="${PSLP_VERSION}")
 

diff --git a/LICENSE b/LICENSE
@@ -186,7 +186,7 @@
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
 
-   Copyright 2025 Daniel Cederberg
+   Copyright 2025-2026 Daniel Cederberg
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

diff --git a/include/PSLP/PSLP_API.h b/include/PSLP/PSLP_API.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/PSLP/PSLP_sol.h b/include/PSLP/PSLP_sol.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/PSLP/PSLP_stats.h b/include/PSLP/PSLP_stats.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Activity.h b/include/core/Activity.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Bounds.h b/include/core/Bounds.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Constraints.h b/include/core/Constraints.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/CoreTransformations.h b/include/core/CoreTransformations.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Debugger.h b/include/core/Debugger.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Locks.h b/include/core/Locks.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Matrix.h b/include/core/Matrix.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Numerics.h b/include/core/Numerics.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Postsolver.h b/include/core/Postsolver.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Problem.h b/include/core/Problem.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/RowColViews.h b/include/core/RowColViews.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/State.h b/include/core/State.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Tags.h b/include/core/Tags.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/Workspace.h b/include/core/Workspace.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/debug_macros.h b/include/core/debug_macros.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/glbopts.h b/include/core/glbopts.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/radix_sort.h b/include/core/radix_sort.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/core/utils.h b/include/core/utils.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/data_structures/Binary_search.h b/include/data_structures/Binary_search.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/data_structures/Memory_wrapper.h b/include/data_structures/Memory_wrapper.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/data_structures/Vec_macros.h b/include/data_structures/Vec_macros.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/data_structures/dVec.h b/include/data_structures/dVec.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/data_structures/iVec.h b/include/data_structures/iVec.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/data_structures/u16Vec.h b/include/data_structures/u16Vec.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/DTonsEq.h b/include/explorers/DTonsEq.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/Parallel_cols.h b/include/explorers/Parallel_cols.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/Parallel_rows.h b/include/explorers/Parallel_rows.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/Primal_propagation.h b/include/explorers/Primal_propagation.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/SimpleReductions.h b/include/explorers/SimpleReductions.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/Simple_dual_fix.h b/include/explorers/Simple_dual_fix.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/StonCols.h b/include/explorers/StonCols.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/include/explorers/Timer.h b/include/explorers/Timer.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/Activity.c b/src/core/Activity.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/Constraints.c b/src/core/Constraints.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/CoreTransformation.c b/src/core/CoreTransformation.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/Debugger.c b/src/core/Debugger.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/Locks.c b/src/core/Locks.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/Matrix.c b/src/core/Matrix.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *
@@ -27,6 +27,9 @@
 #include "stdlib.h"
 #include "string.h"
 
+/* forward declaration */
+static inline void remove_explicit_zeros(Matrix *A);
+
 Matrix *matrix_new(const double *Ax, const int *Ai, const int *Ap, size_t n_rows,
                    size_t n_cols, size_t nnz)
 {
@@ -114,9 +117,35 @@ Matrix *matrix_new_no_extra_space(const double *Ax, const int *Ai, const int *Ap
         A->p[i].end = Ap[i + 1];
     }
 
+    /* the presolver assumes that only nonzero entries are stored */
+    remove_explicit_zeros(A);
+
     return A;
 }
 
+static inline void remove_explicit_zeros(Matrix *A)
+{
+    int i, j, shift;
+    for (i = 0; i < A->m; ++i)
+    {
+        shift = 0;
+        for (j = A->p[i].start; j < A->p[i].end; ++j)
+        {
+            if (A->x[j] == 0.0)
+            {
+                shift++;
+            }
+            else if (shift > 0)
+            {
+                A->x[j - shift] = A->x[j];
+                A->i[j - shift] = A->i[j];
+            }
+        }
+        A->p[i].end -= shift;
+        A->nnz -= (size_t) shift;
+    }
+}
+
 Matrix *transpose(const Matrix *A, int *work_n_cols)
 {
     Matrix *AT = matrix_alloc(A->n, A->m, A->nnz);
@@ -433,7 +462,6 @@ double insert_or_update_coeff(Matrix *A, int row, int col, double val, int *row_
     // -----------------------------------------------------------------
     if (ABS(val) > ZERO_TOL)
     {
-        // assert(!IS_ZERO_FEAS_TOL(val));
         if (insertion == end)
         {
             A->x[insertion] = val;

diff --git a/src/core/Postsolver.c b/src/core/Postsolver.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/Presolver.c b/src/core/Presolver.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *
@@ -305,6 +305,7 @@ Presolver *new_presolver(const double *Ax, const int *Ai, const int *Ap, size_t
     presolver->stgs = stgs;
     presolver->prob = new_problem(constraints, obj);
     presolver->stats = init_stats(A->m, A->n, nnz);
+    presolver->stats->nnz_removed_trivial = nnz - (size_t) A->nnz; /* explicit 0's */
     presolver->reduced_prob =
         (PresolvedProblem *) ps_calloc(1, sizeof(PresolvedProblem));
     DEBUG(run_debugger(constraints, false));

diff --git a/src/core/Problem.c b/src/core/Problem.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *

diff --git a/src/core/State.c b/src/core/State.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Daniel Cederberg
+ * Copyright 2025-2026 Daniel Cederberg
  *
  * This file is part of the PSLP project (LP Presolver).
  *