[Tutor] Finding prime numbers script runs much faster when run via bash shell than idle
Jaime Gago
contact at jaimegago.com
Sat Apr 2 07:10:47 CEST 2011
Hello there,
Totally new to python with some *nix scripting knowledge.
I wrote a simple piece of code as an exercise to an online -free- class that finds prime numbers. When I run it via IDLE it's taking way more time than if I run it via a (bash) shell (on Os X 10.6) while doing $>python -d mypp.py
I'm really curious from a performance perspective as to what could cause such a noticeable difference.
Thank you very much!
Here is the code
-------
#Finding the 1000th Prime number
#
#
### STATE VARIABLES INITIALIZATION ###
tested_number = 3
testing_against = 3
prime_counter = 1
### Starting the loop ##
### Number of prime numbers we want to find ##
while(prime_counter < 1000):
### Testing if there is remainder of the division by the testing_against var
while ((tested_number%testing_against != 0) and (testing_against < tested_number)):
testing_against=testing_against + 1
if (tested_number != testing_against):
x = 1
else:
prime_counter = prime_counter + 1
print prime_counter, 'found so far'
## Incrementing the tested number by 2 so we only test odd numbers
tested_number = tested_number + 2
## Reinitialization of the testing_against var to reenter the second loop in the required var state
testing_against = 3
## Printing the prime number
print (tested_number - 2), 'is the 1000th prime number'
------
More information about the Tutor
mailing list