I'm trying to build a simple web app for generating random numbers using IBMQ (Qiskit) and Streamlit. However, if there is no IBMQ saved account it should wait for the user to enter the API token and if the token is valid then proceed further and load IBMQ backends. Below is the code which I have written:
filename.py
# -*- coding: utf-8 -*-
"""
Created on Sun Jan 31 01:30:00 2021
@author: ShadabHussain
"""
import warnings
warnings.filterwarnings("ignore")
import requests
import streamlit as st
# IBMQ
from qiskit import QuantumRegister, ClassicalRegister, QuantumCircuit, execute, IBMQ
from qiskit.tools.monitor import job_monitor
st.set_page_config(page_title='QRNG', page_icon=None, layout='centered', initial_sidebar_state='auto')
st.markdown("<h1 style='text-align: center; color: black;'>Quantum Random Number Generator</h1>", unsafe_allow_html=True)
quantum_computer = st.sidebar.selectbox("Select Quantum Computer Type", ['IBMQ'])
subheader = "using "+ quantum_computer
st.markdown(f"<h1 style='text-align: center; color: black;'>{subheader}</h1>", unsafe_allow_html=True)
def about(quantum_computer):
if quantum_computer == "IBMQ":
text = "Qiskit is an open source SDK for working with quantum computers at the level of pulses, circuits and application modules. It accelerates the development of quantum applications by providing the complete set of tools needed for interacting with quantum systems and simulators."
link = 'https://qiskit.org/'
link_text = 'For Qiskit Documentation'
st.markdown(f"<body style='text-align: center; color: black;'>{text}</body>", unsafe_allow_html=True)
st.markdown(f"<h4 align='center'> <a href={link}>{link_text}</a> </h4>", unsafe_allow_html=True)
about(quantum_computer)
def ibmq_qrng(minimum, maximum):
q = QuantumRegister(num_q, 'q')
c = ClassicalRegister(num_q, 'c')
circuit = QuantumCircuit(q, c)
circuit.h(q) # Applies hadamard gate to all qubits
circuit.measure(q, c) # Measures all qubits
job = execute(circuit, backend, shots=1)
counts = job.result().get_counts()
result = int(counts.most_frequent(), 2)
result1 = minimum + result % (maximum+1 - minimum)
return result1
if quantum_computer == "IBMQ":
api_key = None
try:
IBMQ.load_account()
except Exception as e:
api_key = st.sidebar.text_input("Enter IBMQ API Key")
if api_key != None:
IBMQ.save_account(api_key, overwrite=True)
IBMQ.load_account()
provider = IBMQ.get_provider(hub='ibm-q')
device = st.sidebar.selectbox("Select Quantum Device", [str(each) for each in provider.backends()])
backend = provider.get_backend(device)
if device == "ibmq_qasm_simulator":
num_q = 32
else:
num_q = 5
minimum = st.sidebar.number_input("Minimum Random Number", value=0)
maximum = st.sidebar.number_input("Maximum Random Number", min_value=minimum+1, value=minimum+1)
num_rand_numbers = st.sidebar.number_input("Number of Random Numbers to be Generated", min_value=1, value=1)
def display_result(result1):
if 'result1' in locals():
st.markdown(f"<h2 style='text-align: center; color: black;'>Sampling {num_rand_numbers} random number between {minimum} and {maximum}: {result1}</h2>", unsafe_allow_html=True)
if st.sidebar.button("Generate Random Number"):
if num_rand_numbers <1:
st.markdown(f"<h3 style='text-align: center; color: black;'>Please enter number of random numbers to be generated 1 or greater then 1</h3>", unsafe_allow_html=True)
else:
if quantum_computer == "IBMQ":
if num_rand_numbers==1:
result1 = ibmq_qrng(minimum, maximum)
else:
result1 = []
for i in range(num_rand_numbers):
result1.append(ibmq_qrng(minimum, maximum))
display_result(result1)
else:
st.markdown(f"<h3 style='text-align: center; color: black;'>Click on 'Generate Random Number' button</h3>", unsafe_allow_html=True)
For running the above code you should have IBMQ API token (https://quantum-computing.ibm.com/account) and python installed on your system with the below dependencies:
pip install qiskit streamlit
Command to run the code:
streamlit run filename.py
When I'm running the app, I'm getting the following error:
Is there any better way of exception handling for qiskit and streamlit?
streamlitbehaves is different, as the streamlit text_input option doesn't wait for the input and it moves to the next block of coding coz of which exception is not getting handled here in a better way. Also, the solution which you suggested before of running the loop 3 times for handling exception was not very much ideal for exception handling, I was looking for a better way but maybe coz of limitation with Qiskit we are not able to do it $\endgroup$