Compound Arithmetic and Assignment

Compound arithmetic and assignment statements combine an arithmetic operation and assignment, replacing a statement such as

 x = x op y;

with the more compact compound form

 x op= y;

For example, x = x + 1; may be replaced with x += 1;. This works for all types that support arithmetic, including the scalar types int, real, complex, the real matrix types vector, row_vector, and matrix, and the complex matrix types, complex_vector, complex_row_vector, and complex_matrix.

Compound addition and assignment

Compound addition and assignment works wherever the corresponding addition and assignment would be well formed.

void operator+=(T x, U y)
x += y is equivalent to x = x + y. Defined for all types T and U where T = T + U is well formed.

Available since 2.17, complex signatures added in 2.30

Compound subtraction and assignment

Compound addition and assignment works wherever the corresponding subtraction and assignment would be well formed.

void operator-=(T x, U y)
x -= y is equivalent to x = x - y. Defined for all types T and U where T = T - U is well formed.

Available since 2.17, complex signatures added in 2.30

Compound multiplication and assignment

Compound multiplication and assignment works wherever the corresponding multiplication and assignment would be well formed.

void operator*=(T x, U y)
x *= y is equivalent to x = x * y. Defined for all types T and U where T = T * U is well formed.

Available since 2.17, complex signatures added in 2.30

Compound division and assignment

Compound division and assignment works wherever the corresponding division and assignment would be well formed.

void operator/=(T x, U y)
x /= y is equivalent to x = x / y. Defined for all types T and U where T = T / U is well formed.

Available since 2.17, complex signatures added in 2.30

Compound elementwise multiplication and assignment

Compound elementwise multiplication and assignment works wherever the corresponding multiplication and assignment would be well formed.

void operator.*=(T x, U y)
x .*= y is equivalent to x = x .* y. Defined for all types T and U where T = T .* U is well formed.

Available since 2.17, complex signatures added in 2.30

Compound elementwise division and assignment

Compound elementwise division and assignment works wherever the corresponding division and assignment would be well formed.

void operator./=(T x, U y)
x ./= y is equivalent to x = x ./ y. Defined for all types T and U where T = T ./ U is well formed.

Available since 2.17, complex signatures added in 2.30