Python随机函数似乎总是生成与最大数字长度相同的数字

Question

I'm new to Python. Trying to generate a random number of random numbers and write it to file. I want the default order to be ascending, so in my loop I each time add the "number" chosen randomly in the previous iteration as my minimum value for the next random number (hope that makes sense):

    # Create random number of random integers and write to file 1:
number = 0  # used later
records = random.randrange(1,100)  # randomly decide how many integers to create (up to 100).
for index in range(1,records):
    # randomly create integer between last number created (to ensure correct sort) and 1 million.
    number = random.randrange(number,100000)
    # write it to file:
    f1.write(str(number) + "\n")
    print(number)

The weird thing is that my output seems to almost always be random numbers but aside from maybe the first 2 or 3 it will immediately jump to a 5 digit number, and then within 4 or 5 iterations it hits and then just repeats the max number (99999) - the following is a common output:

50518 84384 87787 91203 91286 92638 93266 97371 99986 99993 99998 99998 99998 99999 99999 99999 99999 99999 99999 99999 99999 99999 99999 99999 99999 99999 99999 99999 99999

Why does the max number get hit so easily within a random range?

Answer 1

Your issue is you reduce the amount of numbers that can be generated from each time as you set the minimum value to the last number generated, this increase the likely hood of generating higher numbers as the minimum keeps being raised.

Instead like others have suggested you should use the random modules sample method which states:

Return ak length list of unique elements chosen from the population sequence or set. Used for random sampling without replacement.

import random
number = 0  # used later
records = random.randrange(1,100)  # randomly decide how many integers to create (up to 100).
numbers = []
for index in range(1,records):
    print(f'generating numbers between {number} and 100000' )
    number = random.randrange(number,100000)
    numbers.append(number)
    #print(number)
print(numbers)
print(sorted(random.sample(range(100000), records)))

OUTPUT

generating numbers between 0 and 100000
generating numbers between 11137 and 100000
generating numbers between 54933 and 100000
generating numbers between 77429 and 100000
generating numbers between 98305 and 100000
generating numbers between 99167 and 100000
generating numbers between 99825 and 100000
generating numbers between 99842 and 100000
generating numbers between 99949 and 100000
generating numbers between 99957 and 100000
generating numbers between 99962 and 100000
generating numbers between 99969 and 100000
[11137, 54933, 77429, 98305, 99167, 99825, 99842, 99949, 99957, 99962, 99969, 99989]
[831, 7001, 18454, 21526, 25156, 29657, 45299, 46796, 61326, 67692, 86185, 90140, 93899]