Qulacs

New features
* Add gpu version of `state_add` and `multiply_coef` (118, thanks to puyokw )

Updates
* Add tests for `state_add` and `multiply_coef` (118, thanks to puyokw )
* Update LICENSE (123, thanks to TenninYan )

Bug fixes
* Fix gpu version of load function: add `copy_quantum_state_from_cppstate_host` in `gpusim` (118, thanks to puyokw )
* Bugfix for GPU codes (120, thanks to corryvrequan )
* Enabled some functions (on parametric quantum gate and quantum gate base) which used to be available only in cpp ver. of qulacs, also in python ver. (124, thanks to corryvrequan )

New features
* New quantum gate `ReversibleBooleanGate`, which supplies easy way to implement classical reversible function as an quantum gate(104, thanks to corryvrequan )
* Implementation of new gates, `StateReflection`, which is frequently used in algorithms such as Grover's search or HHL, and `SparseMatrix` (108, thanks to corryvrequan )
* New methods `QuantumStateCpu::add_state` and `QuantumStateCpu::multiply_coef` for use of analysis (111, thanks to corryvrequan )
* New methods in `multi_qubit_dense_matrix_gate_host` to be called when the number of target qubits is small (112, thanks to puyokw )

Updates
* Changes in return value policy of copy function and gate factory from `automatic_reference` to `take_ownership` (101, thanks to corryvrequan )
* New test class for pointer handling, checking if there is no segfault in typical codes (101, thanks to corryvrequan )
* New constructor for `PauliOperator` in python and new methods `GeneralQuantumOperator.is_hermitian()`, to check if an operator is hermitian (103, thanks to hal0taso )
* New initialization to `expectation_value_single_qubit_Pauli_operator_hos` (105, thanks to puyokw )

Bug fixes
* Bugfix of path (95, thanks to kwkbtr )
* GCC version updates, changes in instruction and typo fixed in `README`(96, 97, and 98, thanks to yoooopeeee , corryvrequan )
* Bugfix of CI travis test (100, thanks to y-yu )
* Bugfix in `QuantumState::get_zero_probability` (107, thanks to corryvrequan )
* Bugfix in `QuantumState::get_marginal_probability` (109 , thanks to corryvrequan )
* Bugfix of the GPU codes not been called when calculating expectation values (114, thanks to puyokw )

Some fix of the document.

New feature
- GPU support! (huge thanks to puyokw, corryvrequan!)

Updates
- Tutorial (thanks corryvrequan!)
- Set vector of QuantumState from numpy array(thanks corryvrequan, mshrn!)
- added Adaptive gate(61, thanks corryvrequan!)
- added a new function get_gate_count for getting the number of gates in a circuit(62, thanks kosukemtr, corryvrequan!)
- add get_gate function in QuantumCircuit class(54, thanks kosukemtr, corryvrequan!)
- Making PauliOperator class availalble to use some limited operation for non hermitian operators(thanks! hal0taso)
- Change memory policy in quantum state(hanks corryvrequan!)
- CI test for pip (thanks, y-yu!)

Bug Fixes
- When calling add_gate kernel crashes (63, thanks kosukemtr, corryvrequan!)

This release note includes all updates, bugfixes since qulacs release.

Updates
- Register PyPI (thanks TenninYan!)
- Install CI tools (thanks TenninYan and y-yu!)
- Improve installation script for more versions of CMake, gcc, python (thanks corryvrequan, TenninYan, and yurisan!)
- Improve and translate documentation (thanks corryvrequan, TenninYan, and kamakiri01!)
- Rename Hamiltonian class to Observable (thanks corryvrequan!)
- Add utility functions to Observable class (thanks hal0taso, corryvrequan!)

Bug Fixes
- When calling ProbabilisticGate kernel crashes (45, thanks corryvrequan!)
- The output values of transition_amplitde_... function are wrong (37, thanks corryvrequan!)
- Install fails (35, thanks yurisan!)
- python crashing after calling qulacs.observable.add_operator(mpt) (34, thanks hal0taso!)