Quantum Architectures: Quantum Circuit Viewer

QASM is a simple text-format language for describing acyclic quantum circuits composed from single qubit, multiply controlled single-qubit gates, multiple-qubit, and multiple-qubit controlled multiple-qubit gates.
qasm2circ is a package which converts a QASM file into a graphical depiction of the quantum circuit, using standard quantum gate symbols (and other user-defined symbols). This is done using latex (specifically, xypic), to produce high-quality output in epsf, pdf, or png formats.
Figures of quantum circuits in the book "Quantum Computation and Quantum Information," by Nielsen and Chuang, were produced using an earlier version of this package.

Download distribution here (zip) or (tgz) (the distribution includes all the examples).

Current version = 1.4 (Released 14-Mar-05)
[ home | Example 1 | Example 2 | Example 3 | Example 4 | Example 5 | Example 6 | Example 7 | Example 8 | Example 9 | Example 10 | Example 11 | Example 12 | Example 13 | Example 14 | Example 15 | Example 16 | Example 18 | Example 17 | qasm specification | Installation instructions ]

QASM Specification

QASM instructions are as follows. Lines begining with '#' are comments. All other lines should be of the form op args where op-args pairs are:

qubit   name,initval
cbit    name,initval
measure qubit
H       qubit
X       qubit
Y       qubit
Z       qubit
S       qubit
T       qubit
nop     qubit
zero    qubit
discard qubit
slash   qubit
dmeter  qubit
cnot    ctrl,target
c-z     ctrl,target
c-x     ctrl,target
toffoli ctrl1,ctrl2,target
ZZ      b1,b2
SS      b1,b2
swap    b1,b2
Utwo    b1,b2
space   qubit
def     opname,nctrl,texsym
defbox  opname,nbits,nctrl,texsym

Where:

def     - define a custom controlled single-qubit operation, with
opname  = name of gate operation
nctrl   = number of control qubits
texsym  = latex symbol for the target qubit operation
defbox  - define a custom muti-qubit-controlled multi-qubit operation, with
opname  = name of gate operation
nbits   = number of qubits it acts upon
nctrl   = number of control qubits
texsym  = latex symbol for the target qubit operation
qubit   - define a qubit with a certain name (all qubits must be defined)
name    = name of the qubit, eg q0 or j2 etc
initval = initial value (optional), eg 0
cbit    - define a cbit with a certain name (all cbits must be defined)
name    = name of the cbit, eg c0
initval = initial value (optional), eg 0
H       - single qubit operator ("hadamard")
X       - single qubit operator 
Y       - single qubit operator 
Z       - single qubit operator
S       - single qubit operator
T       - single qubit operator
nop     - single qubit operator, just a wire
space   - single qubit operator, just an empty space
dmeter  - measure qubit, showing "D" style meter instead of rectangular box
zero    - replaces qubit with |0> state
discard - discard qubit (put "|" vertical bar on qubit wire)
slash   - put slash on qubit wire
measure - measurement of qubit, gives classical bit (double-wire) output
cnot    - two-qubit CNOT
c-z     - two-qubit controlled-Z gate
c-x     - two-qubit controlled-X gate
swap    - two-qubit swap operation 
Utwo    - two-qubit operation U
ZZ      - two-qubit controlled-Z gate, symmetric notation; two filled circles
SS      - two-qubit gate, symmetric; open squares
toffoli - three-qubit Toffoli gate

---

Installation instructions

-----------------------------------------------------------------------------
REQUIREMENTS:

- latex2e with xypic (included in tetex)
- python version 2.3 or greater
- ghostscript (and epstopdf)
- netpbm (for creation of png files)

-----------------------------------------------------------------------------
LIST OF FILES:

README  - this file
meter.epsf     - picture of measurement meter
qasm2pdf - script to create PDF from QASM file
qasm2png - script to create PNG from QASM file
qasm2tex.py - main python program to convert QASM to latex file
samples - directory containing examples
xyqcirc.tex - latex macros necessary to compile the latex files

-----------------------------------------------------------------------------
INSTALLATION INSTRUCTIONS:

untar/unzip this distribution; it creates the directory qasm2circ with
all of the files.  Copy your qasm file into this directory, and run
qasm2pdf or qasm2png to create the desired output.  You may also run
"python qasm2tex.py foo.qasm" to generate just the tex file (it will
appear on stdout).