Improve execution speed

[changxuqing]

The operations of converting characters to ASCII values and generating a list of bits can be combined into one loop, reducing the number of passes.

[changxuqing]

def string_to_bitlist(data):
ord_ = ord
result = []
append = result.append
for ch in data:
ascii_value = ord_(ch)
for i in range(7, -1, -1):
append((ascii_value >> i) & 1)
return result

def string_to_bitlist2(data):
data = [ord(c) for c in data]
result = []
for ch in data:
i = 7
while i >= 0:
if ch & (1 << i) != 0:
result.append(1)
else:
result.append(0)
i -= 1
return result

import time

def test_method1(data):
start_time = time.time()
result = string_to_bitlist(data)
end_time = time.time()
print("Method 1 Execution Time:", end_time - start_time)
return result

def test_method2(data):
start_time = time.time()
result = string_to_bitlist2(data)
end_time = time.time()
print("Method 2 Execution Time:", end_time - start_time)
return result

import timeit

test_string = "Hello, World!" *1000
number_of_executions = 1000
time1 = timeit.timeit('string_to_bitlist(test_string)', globals=globals(), number=number_of_executions)
print(f"string_to_bitlist: {time1} seconds")
time2 = timeit.timeit('string_to_bitlist2(test_string)', globals=globals(), number=number_of_executions)
print(f"string_to_bitlist2: {time2} seconds")

Hi ,@richtja I compared the speed of the two methods, and the results show that the speed is faster than before when dealing with large data.Here are the results

string_to_bitlist: 8.632775765028782 seconds
string_to_bitlist2: 10.137682066997513 seconds

[richtja]

Hi @changxuqing, thank you for your changes. It LGTM. Can you please do a rebase to master? It should solve the CI issues.

[richtja]

Hi @changxuqing, is there any reason for closing this?