How to generate exponentially increasing range in Python
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I want to test the performance of some code using an exponentially increasing value.  So that as an extra digit is added to the numbers_size the increment is multiplied by 10.  This is how I'm doing it so far but it looks a bit hacky.  Suggestions for improvments without introducing non-standard libraries?

    numbers_size = 100
    increment = 100
    numbers_range = 1000000000
    while numbers_size < numbers_range:
        t = time.time()
        test( numbers_size )
        taken_t = time.time() - t
        print numbers_size, test', taken_t
    
        increment = 10 ** (len(str(numbers_size))-1)
        numbers_size += increment

