First 30 Million Prime Numbers

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After creating some code, I’ve finally got my computer to calculate the first 30 Million Prime Numbers. It only took 8.3 hours, according to the timer I set up.

Here’s my code:


from timeit import default_timer
start = default_timer()
import math
text_file = open("10,000,000 to 20,000,000.txt", "w")
text_file1 = open("10,000,000 to 20,000,000 with rowNumbers.txt", "w")
text_file2 = open("20,000,000 to 30,000,000.txt", "w")
text_file3 = open("20,000,000 to 30,000,000 with rowNumbers.txt", "w")
text_output = open("Output.txt", "w")
text_output.write("Started: "+ str(default_timer() - start) + " seconds\n")

primes = [2, 3]
print("This file was made for cornerspots.com\n1. 2\n2. 3")
text_file.write("This file was made for cornerspots.com\n10,000,000th prime to 20,000,000th prime\n")
text_file1.write("This file was made for cornerspots.com\n10,000,000th prime to 20,000,000th prime\n")
text_file2.write("This file was made for cornerspots.com\n10,000,000th prime to 20,000,000th prime\n")
text_file3.write("This file was made for cornerspots.com\n10,000,000th prime to 20,000,000th prime\n")
number = 1
rowNumber = 2

while rowNumber < 30000000: #30,000,000
    isPrime = True
    number += 2

    for prime in primes:
        # if number is bigger than the sqrt of num we're checking
        if prime > math.sqrt(number):
            break
        # is not a prime
        if number % prime == 0:
            isPrime = False
            break

    if isPrime:
        rowNumber += 1
        primes.append(number)
        print(str(rowNumber) + ". " + str(number))
        if (rowNumber >= 10000000 and rowNumber <= 20000000):
            text_file.write(str(number) + "\n")
            text_file1.write(str(rowNumber) + ". " + str(number) + "\n")

        if (rowNumber >= 20000000 and rowNumber <= 30000000):
            text_file2.write(str(number) + "\n")
            text_file3.write(str(rowNumber) + ". " + str(number) + "\n")
            
text_file.close()
text_file1.close()
text_file2.close()
text_file3.close()
text_output.write("Ended: " + str(default_timer() - start) + "seconds")

 

Now I know that there was probably an easier way to do this, but I decided to split up the files into 10 Million each because I noticed that notepad was starting to get a little laggy when I
If you're looking for the first 10 Million, look at the post right before this one. Also, if you use notepad++ to open the files, then there is almost no lag.
If you try to open this with normal notepad, you have to wait around 1 minute for the whole thing to load. If notepad says it's not responding, just wait. It will open eventually.

10MillionthPrime_To_20MillionthPrime_withoutrowNumbers

10MillionthPrime_To_20MillionthPrime_withRowNumbers

20MillionthPrime_To_30MillionthPrime_withoutRowNumbers

20MillionthPrime_To_30MillionthPrime_withRowNumbers

 

 

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