diff --git a/libs/main/containers/pivector2d.h b/libs/main/containers/pivector2d.h
index 537ded76..ed8d0dc6 100644
--- a/libs/main/containers/pivector2d.h
+++ b/libs/main/containers/pivector2d.h
@@ -705,6 +705,11 @@ public:
 		size_t st_, sz_;
 
 	public:
+		inline RowConst(const PIVector2D<T>::Row & r): p_(r.p_) {
+			st_ = r.st_;
+			sz_ = r.sz_;
+		}
+
 		//! \~english Size of the row (number of columns).
 		//! \~russian Размер строки (количество столбцов).
 		inline size_t size() const { return sz_; }
@@ -875,6 +880,12 @@ public:
 		size_t step_, col_, sz_;
 
 	public:
+		inline ColConst(const PIVector2D<T>::Col & c): p_(c.p_) {
+			step_ = c.step_;
+			col_  = c.col_;
+			sz_   = c.sz_;
+		}
+
 		//! \~english Size of the column (number of rows).
 		//! \~russian Размер столбца (количество строк).
 		inline size_t size() const { return sz_; }
@@ -1130,18 +1141,6 @@ public:
 	//! \~russian Если массив был пуст, количество столбцов устанавливается равным размеру исходной строки.
 	//! В противном случае копируется только `min(cols(), other.size())` элементов; остальные элементы новой строки инициализируются по
 	//! умолчанию. \sa PIVector::push_back()
-	inline PIVector2D<T> & addRow(const Row & other) {
-		if (cols_ == 0) cols_ = other.sz_;
-		const size_t sz = piMin<size_t>(cols_, other.sz_);
-		const size_t ps = mat.size();
-		mat.resize(mat.size() + cols_);
-		mat._copyRaw(mat.data(ps), other.data(), sz);
-		rows_++;
-		return *this;
-	}
-
-	//! \~english Appends a new row to the bottom of the array from a read-only RowConst object.
-	//! \~russian Добавляет новую строку в конец массива из объекта RowConst только для чтения.
 	inline PIVector2D<T> & addRow(const RowConst & other) {
 		if (cols_ == 0) cols_ = other.sz_;
 		const size_t sz = piMin<size_t>(cols_, other.sz_);
@@ -1164,6 +1163,72 @@ public:
 		return *this;
 	}
 
+	//! \~english Appends a new column to the right of the array from a \a PIVector.
+	//! \~russian Добавляет новую строку в конец массива из \a PIVector.
+	inline PIVector2D<T> & addColumn(const ColConst & other) {
+		if (other.size() == 0) return *this;
+		if (size() == 0) {
+			_resizeRaw(other.size(), 1);
+			for (size_t r = 0; r < other.size(); ++r) {
+				element(r, 0) = other[r];
+			}
+			return *this;
+		}
+
+		const size_t oldCols = cols_;
+		const size_t newCols = oldCols + 1;
+		const size_t newSize = rows_ * newCols;
+
+		mat._resizeRaw(newSize);
+
+		for (size_t r = rows_ - 1; r > 0; --r) {
+			T * src = mat.data(r * oldCols);
+			T * dst = mat.data(r * newCols);
+			memmove(dst, src, oldCols * sizeof(T));
+			if (r < other.size()) {
+				dst[oldCols] = other[r];
+			} else {
+				dst[oldCols] = T();
+			}
+		}
+		mat[oldCols] = other[0];
+
+		cols_        = newCols;
+		return *this;
+	}
+
+	inline PIVector2D<T> & addColumn(const PIVector<T> & other) {
+		if (other.size() == 0) return *this;
+		if (size() == 0) {
+			_resizeRaw(other.size(), 1);
+			for (size_t r = 0; r < other.size(); ++r) {
+				element(r, 0) = other[r];
+			}
+			return *this;
+		}
+
+		const size_t oldCols = cols_;
+		const size_t newCols = oldCols + 1;
+		const size_t newSize = rows_ * newCols;
+
+		mat._resizeRaw(newSize);
+
+		for (size_t r = rows_ - 1; r > 0; --r) {
+			T * src = mat.data(r * oldCols);
+			T * dst = mat.data(r * newCols);
+			memmove(dst, src, oldCols * sizeof(T));
+			if (r < other.size()) {
+				dst[oldCols] = other[r];
+			} else {
+				dst[oldCols] = T();
+			}
+		}
+		mat[oldCols] = other[0];
+
+		cols_        = newCols;
+		return *this;
+	}
+
 	//! \~english Resizes the 2D array to new dimensions.
 	//! \~russian Изменяет размер двумерного массива.
 	//! \param rows New number of rows.
diff --git a/tests/math/testpivector2d.cpp b/tests/math/testpivector2d.cpp
index 29831aab..c8d3bb87 100644
--- a/tests/math/testpivector2d.cpp
+++ b/tests/math/testpivector2d.cpp
@@ -379,6 +379,146 @@ TEST_F(Vector2DTest, addRow_with_shorter_vector_uses_min) {
 	}
 }
 
+// ==================== ADD COLUMN TESTS ====================
+
+TEST_F(Vector2DTest, addColumn_appends_column_to_empty) {
+	PIVector2D<int> empty;
+	PIVector<int> newCol(5);
+	for (size_t i = 0; i < 5; ++i)
+		newCol[i] = static_cast<int>(100 + i);
+
+	empty.addColumn(newCol);
+
+	EXPECT_EQ(empty.rows(), 5);
+	EXPECT_EQ(empty.cols(), 1);
+	for (size_t r = 0; r < 5; ++r) {
+		EXPECT_EQ(empty.element(r, 0), static_cast<int>(100 + r));
+	}
+}
+
+TEST_F(Vector2DTest, addColumn_appends_column_to_existing) {
+	size_t oldRows = vec.rows();
+	size_t oldCols = vec.cols();
+
+	PIVector<int> newCol(oldRows, 999);
+	vec.addColumn(newCol);
+
+	EXPECT_EQ(vec.rows(), oldRows);
+	EXPECT_EQ(vec.cols(), oldCols + 1);
+
+	// Check that old data is preserved
+	for (size_t r = 0; r < oldRows; ++r) {
+		for (size_t c = 0; c < oldCols; ++c) {
+			EXPECT_EQ(vec.element(r, c), static_cast<int>(r * COLS_COUNT_INIT + c));
+		}
+	}
+
+	// Check new column
+	for (size_t r = 0; r < oldRows; ++r) {
+		EXPECT_EQ(vec.element(r, oldCols), 999);
+	}
+}
+
+TEST_F(Vector2DTest, addColumn_with_shorter_vector_uses_min) {
+	size_t oldRows  = vec.rows();
+	size_t oldCols  = vec.cols();
+	size_t shortLen = oldRows - 10;
+	PIVector<int> shortCol(shortLen, 777);
+
+	vec.addColumn(shortCol);
+
+	EXPECT_EQ(vec.cols(), oldCols + 1);
+
+	// First shortLen rows should be 777
+	for (size_t r = 0; r < shortLen; ++r) {
+		EXPECT_EQ(vec.element(r, oldCols), 777);
+	}
+	// Remaining rows should be default-initialized (0)
+	for (size_t r = shortLen; r < oldRows; ++r) {
+		EXPECT_EQ(vec.element(r, oldCols), 0);
+	}
+}
+
+TEST_F(Vector2DTest, addColumn_with_longer_vector_truncates) {
+	size_t oldRows = vec.rows();
+	size_t oldCols = vec.cols();
+	size_t longLen = oldRows + 10;
+	PIVector<int> longCol(longLen, 555);
+
+	vec.addColumn(longCol);
+
+	EXPECT_EQ(vec.cols(), oldCols + 1);
+
+	// All rows should be 555 (only first oldRows elements are used)
+	for (size_t r = 0; r < oldRows; ++r) {
+		EXPECT_EQ(vec.element(r, oldCols), 555);
+	}
+}
+
+TEST_F(Vector2DTest, addColumn_with_empty_source_does_nothing_on_empty) {
+	PIVector2D<int> empty;
+	PIVector<int> emptyCol;
+
+	empty.addColumn(emptyCol);
+	EXPECT_TRUE(empty.isEmpty());
+	EXPECT_EQ(empty.rows(), 0);
+	EXPECT_EQ(empty.cols(), 0);
+}
+
+TEST_F(Vector2DTest, addColumn_with_empty_source_adds_default_column) {
+	auto oldVec           = vec;
+
+	vec.addColumn({});
+
+	EXPECT_EQ(vec.cols(), oldVec.cols());
+	EXPECT_EQ(vec.rows(), oldVec.rows());
+
+	for (size_t r = 0; r < oldVec.rows(); ++r) {
+		for (size_t c = 0; c < oldVec.cols(); ++c) {
+			EXPECT_EQ(vec.element(r, c), oldVec.element(r, c));
+		}
+	}
+}
+
+TEST_F(Vector2DTest, addColumn_with_Col_proxy_works) {
+	auto oldVec           = vec;
+	const size_t colIndex = 5;
+
+	auto srcCol           = oldVec.col(colIndex);
+	vec.addColumn(srcCol);
+
+	EXPECT_EQ(vec.cols(), oldVec.cols() + 1);
+	EXPECT_EQ(vec.rows(), oldVec.rows());
+
+	for (size_t r = 0; r < oldVec.rows(); ++r) {
+		for (size_t c = 0; c < oldVec.cols(); ++c) {
+			EXPECT_EQ(vec.element(r, c), oldVec.element(r, c));
+		}
+	}
+	for (size_t r = 0; r < vec.rows(); ++r) {
+		// EXPECT_EQ(vec.element(r, oldVec.cols()), int());
+		piCout << r << vec.cols() << oldVec.cols() << colIndex;
+		EXPECT_EQ(vec.element(r, oldVec.cols()), oldVec.element(r, colIndex));
+	}
+}
+
+TEST_F(Vector2DTest, addColumn_with_ColConst_proxy_works) {
+	size_t oldRows             = vec.rows();
+	size_t oldCols             = vec.cols();
+
+	const auto & constVec      = vec;
+	auto srcCol                = constVec.col(7);
+	// Need a non-const array to add to
+	PIVector2D<int> mutableVec = vec; // copy
+	mutableVec.addColumn(srcCol);
+
+	EXPECT_EQ(mutableVec.cols(), oldCols + 1);
+
+	for (size_t r = 0; r < oldRows; ++r) {
+		EXPECT_EQ(mutableVec.element(r, oldCols), vec.element(r, 7));
+	}
+}
+
 // ==================== RESIZE TESTS ====================
 class Vector2DResizeTest: public Vector2DTest {
 protected:
@@ -670,7 +810,8 @@ TEST(Vector2DTransposeTest, singleElement_returnsSame) {
 
 TEST(Vector2DTransposeTest, oneRow_becomesOneColumn) {
 	PIVector2D<int> rowVec(1, 5);
-	for (size_t c = 0; c < 5; ++c) rowVec.element(0, c) = static_cast<int>(c);
+	for (size_t c = 0; c < 5; ++c)
+		rowVec.element(0, c) = static_cast<int>(c);
 	auto transposed = rowVec.transposed();
 	EXPECT_EQ(transposed.rows(), 5);
 	EXPECT_EQ(transposed.cols(), 1);
@@ -681,7 +822,8 @@ TEST(Vector2DTransposeTest, oneRow_becomesOneColumn) {
 
 TEST(Vector2DTransposeTest, oneColumn_becomesOneRow) {
 	PIVector2D<int> colVec(5, 1);
-	for (size_t r = 0; r < 5; ++r) colVec.element(r, 0) = static_cast<int>(r);
+	for (size_t r = 0; r < 5; ++r)
+		colVec.element(r, 0) = static_cast<int>(r);
 	auto transposed = colVec.transposed();
 	EXPECT_EQ(transposed.rows(), 1);
 	EXPECT_EQ(transposed.cols(), 5);
@@ -691,7 +833,7 @@ TEST(Vector2DTransposeTest, oneColumn_becomesOneRow) {
 }
 
 TEST_F(Vector2DTest, transposed_doesNotModifyOriginal) {
-	auto original = vec; // копия для сравнения
+	auto original   = vec; // копия для сравнения
 	auto transposed = vec.transposed();
 	// Проверяем, что исходный массив не изменился
 	EXPECT_EQ(vec, original);
@@ -1271,7 +1413,6 @@ TEST_F(Vector2DTest, colconst_proxy_every_returns_true_if_all_match) {
 	auto isLessThanMax    = [&](const int & e) { return e < static_cast<int>(vec.size()); };
 	EXPECT_TRUE(col.every(isLessThanMax));
 	auto isNotEven = [](const int & e) { return e % 2 != 0; };
-	col.forEach([](const int & v) { piCout << v; });
 	EXPECT_FALSE(col.every(isNotEven));
 }