QCAD is a windows-based GUI environment of Quantum Computing Simulation, it will help you to study quantum computations.
This software has following functions.
See Available Quantum Gates. The matrices of the gates are also shown there.
to execute it.Remove installed folder and its contents.
NOTE: QCAD will never touch any registries of your system.
When QCAD is executed, you can see "Edit Window". You can put gates on it.
Circuit Panel is a circuit selector.
You can open it by choosing "Circuit Panel" by "View" menu.
Click a button which shows a circuit that you want to put.
Then the circuit is selected.
Next, Click the edit window, then the circuit is put there.
If the circuit requires parameter, the parameter window will open.
Set all parameters like as control bits, and then push OK.
Walsh Hadamard Gate
Not Gate
Controlled Not Gate
Toffoli (Controlled Controlled Not) Gate
Rotation Gate
Controlled Rotation Gate
Pauli X Gate
Pauli Y Gate
Pauli Z Gate
Swap Gate
Measurement GateGate "Bitbox" are special gates. They are irremovable. You can set the initial value of qubits.
If you want to set initial value of qubit as |0...01>, change state of Bitbox at Q1 to "1",
and "0" for other Bitbox.
If you set Enabled to false, the line become disabled. This function is for exporting an EPS file. You can get EPS file with skipping this line.
You can save and load the circuit data of QCAD by "Save" and "Load" options on "File" menu. A default extension is "qcd".
You can export a designed circuit as EPS(Encapsulated PostScript) file which is suitable for LaTeX or other types of document.
After designing a circuit, choose "Export EPS file".
If you need a bitmap file of a designed circuit, you can export a bitmap file which is what you see at the edit window. After designing a circuit, choose "Export as Bitmap file".
The Menus and their short cuts allow quick access to many operations. The Following menus are available.
The File menu allows access to the operations of saving and loading data, exporting as other formats and quitting QCAD.
Select the "New" option to obtain a new circuit. QCAD will ask you the size of it. If there is an unsaved circuits, the confirm dialog opens, asking for a file name for the designed circuit.
Select the "Open" option to open the designed QCAD file. If there is an unsaved circuits, the confirm dialog opens, asking for a file name for the designed circuit.
Select the "Save" option to save the designed circuit to the file.
If you have not set the name of file, Save Dialog appears and requires the filename.
Select the "Save As" option to save the designed circuit to the file with desired filename. Save Dialog appears and requires the filename.
Select the "Export as EPS file" option to export the designed circuit as the EPS(Encapsulated PostScript) file format. This format is suitable for LaTeX or other document to include.
Select the "Export as Bitmap file" option to export the designed circuit as the Bitmap file format. The current format of the bitmap is the type of 8bit(including 256 colors).
Print the current circuit.
Setup a printer.
Select the "Exit" option to quit designing and close the QCAD. If there is an unsaved circuits, the confirm dialog opens, asking for a file name for the designed circuit.
The View menu allows access to Circuit Panel.
Select the Circuit Panel option to open the circuit panel. See <a href="#HLP000011">Circuit Panel</a> section for more information.
Edit menu allows to the operations which modify the designing circuit.
Select the Undo option to undo the previous operations. You can undo all operations and the number of undo is unlimited (it depends on the size of memory of your system).
Select the Remove option to remove the selected gates.
Edit menu allows to operations to the simulator of the QCAD.
See Simulate Circuit section for details.
The Help menu allows access to the help or version information of the QCAD.
Select the Help option to open the contents of QCAD help file.
Select the Version option to show the version information of the QCAD.
You can simulate a designed circuit on QCAD.
Try "Calc" of "Calc" menu, or hit "F5" key, and QCAD simulate your circuits and show results.
WARNING:
The calculation of the quantum circuits requires huge memory. When the circuit has 32 lines, for example, it will use 64GB. If you try to calculate large circuits, your machine might be in trouble.
From Ver. 1.92, measurement gates has been available. If a circuit contains measurement gates, the "Measurement View" becomes available.
For example, the above circuits involves the following measured result.
The result contains indeces, qubits' status, and the probability that the status to be measured, respectively.
This measurememt DOES NOT achieve real measurement. The measurement gates on QCAD do only set "measurement flags". After the calculation, the measurement is performed.
For example, the following two circuits are equivalent on QCAD.
The format of the exported file is as follows,
#QCAD Result file #ex) Index), (Qubits conf.), (Abs. value), (Re. part), (Im. part) #ex) 0, |00000> , 1.000 , 0.4455 , 0.23 0,|0000000>, 1.000000,1.000000,0.000000 1,|0000001>, 0.000000,0.000000,0.000000 ..... 127,|1111111>, 0.000000,0.000000,0.000000
QCAD has some problems as following.
Copyright (C) 2002 - 2011 QCAD Developers Team
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
THIS SOFTWARE IS PROVIDED ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This work is supported by a grant under the youth section of Exploratory Software Project FY2002 (IPA, Japan). This software was developed at the University of Tokyo and Nagoya University.