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docs/lib2x-m_determinant.md

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+# m_determinant
+
+It can calculate a determinant, a special number that can be calculated from a square matrix.
+
+**Since:** 2.4
+
+## Parameters
+
+- `m` : A square matrix.
+
+## Examples
+
+    use <matrix/m_determinant.scad>;
+
+    assert(
+        m_determinant([
+            [3, 8],
+            [4, 6]
+        ]) == -14
+    );
+
+    assert(
+        m_determinant([
+            [6,  1, 1],
+            [4, -2, 5],
+            [2,  8, 7]
+        ]) == -306
+    );
+
+    assert(
+        m_determinant([
+            [0,  4, 0, -3],
+            [1,  1, 5,  2],
+            [1, -2, 0,  6],
+            [3,  0, 0,  1]
+        ]) == -250
+    );