feat: initial release

Assisted-by: GLM 5.3 Flash

optim/rowblocks_pin_test.go

@@ -0,0 +1,48 @@
+// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
+// SPDX-License-Identifier: MIT
+
+package optim
+
+import (
+	"math"
+	"testing"
+
+	"sourcedock.dev/petrbalvin/tensor/internal/core"
+)
+
+// MinimiseLinearRows hands both standard rows of a two-sided constraint
+// slots in the one backing block, taken in build order. A fixture with
+// a two-sided row and a one-sided row pins the hand-computed optimum,
+// which a row that aliased its neighbour could not reach.
+
+func TestMinimiseLinearRowsTwoSidedConstraint(t *testing.T) {
+	// minimise x1 - 2*x2 over 2 ≤ x1 + x2 ≤ 3 and 0 ≤ x1 ≤ 1: the
+	// objective pushes x2 up and x1 down, so x1 = 0, x2 = 3 and the
+	// optimum is -6.
+	cost, err := core.FromFloats([]float64{1, -2}, 2)
+	if err != nil {
+		t.Fatalf("FromFloats: %v", err)
+	}
+	a, err := core.FromFloats([]float64{1, 1, 1, 0}, 2, 2)
+	if err != nil {
+		t.Fatalf("FromFloats: %v", err)
+	}
+	cons := LinearConstraints{
+		A:     a,
+		Lower: []float64{2, 0},
+		Upper: []float64{3, 1},
+	}
+	x, value, merr := MinimiseLinearRows(cost, cons, LinearProgramOptions{})
+	if merr != nil {
+		t.Fatalf("MinimiseLinearRows: %v", merr)
+	}
+	if math.Abs(value+6) > 1e-9 {
+		t.Fatalf("optimum = %v, want -6", value)
+	}
+	if v := x.FloatAt(0); math.Abs(v) > 1e-9 {
+		t.Fatalf("x1 = %v, want 0", v)
+	}
+	if v := x.FloatAt(1); math.Abs(v-3) > 1e-9 {
+		t.Fatalf("x2 = %v, want 3", v)
+	}
+}