Ok, you were right - just did something similar again, and difference was: It took 0.167999982834 seconds to do randInt 100000 times It took 0.0449998378754 seconds to do random and convert output 100000 times Here's the code: #start code import random, time tInt = time.time() for I in range(1, 100000): iRand = random.randint(1, 100)print "It took " + str(time.time() - tInt) + " seconds to do randInt 100000 times"
tRand = time.time() for I in range(1, 100000): fRand = random.random() iRand = int(fRand * 100)print "It took " + str(time.time() - tRand) + " seconds to do random and convert output 100000 times"
#end code Jacob Kruger Blind Biker Skype: BlindZA '...fate had broken his body, but not his spirit...'----- Original Message ----- From: "R Dinger" <rrdinger@xxxxxxxxxx>
To: <program-l@xxxxxxxxxxxxx> Sent: Monday, October 01, 2012 4:42 PM Subject: [program-l] Re: Python list access speeds
Regarding your random tests: reducing time from 7 seconds to 2.7 is still 2.59 times faster and that could be significant. I vaguely recall your test, but I thought it was much closer. Richard----- Original Message ----- From: "Jacob Kruger" <jacob@xxxxxxxxxxxxx>To: <program-l@xxxxxxxxxxxxx> Sent: Sunday, September 30, 2012 9:36 PM Subject: [program-l] Re: Python list access speeds Reminds me of a test I did - put together two loops where used either random.random() and converted the result to a number ranging from 1 to 100 sort of manually, and then did the same loop, but using random.randint(1, 100), and got them to both operate like 100000 times, and it was actuallyslightly quicker to just use random.random(), but anyway - think differencewas like 2.7 seconds, compared to like 7 seconds. Stay well Jacob Kruger Blind Biker Skype: BlindZA '...fate had broken his body, but not his spirit...'----- Original Message ----- From: "R Dinger" <rrdinger@xxxxxxxxxx>To: "programming" <program-l@xxxxxxxxxxxxx> Sent: Monday, October 01, 2012 1:01 AM Subject: [program-l] Python list access speedsI got to thinking about list access speeds when reading replies to Al's iterator reset question last week, so I decided to do some testing with the timeit module. I tested access by subscript and by direct iteration.I used the following setup code (a list of 500 random numbers) for all thetests. The time to execute the setup code is not included in the timing tests. setup = """ from random import random valList = [] for i in xrange(500): valList.append(random()) """ The following code fragments were tested each running the loop 1 million times. stmt1 = """ for i in range(len(valList)): v = valList[i] """ time: 8.01 sec stmt2 = """ for i in xrange(len(valList)): v = valList[i] """ time: 7.43 sec stmt3 = """ for v in valList: pass """ time: 2.67 sec stmt4 = """ for i, v in enumerate(valList): pass """ time: 6.12 sec So access by subscripting from a list generated by the range function is the slowest. In the second test using xrange (a generator) helped a little, but not much. The third test using direct iteration of the list is clearly much faster. Finally in the last test I used the enumerate object to generate the subscripts in case that was needed by the application in addition to the list value.The timeit module is quite handy, but be careful it can be quite addictiveand lead to late nights testing all sorts of code fragments. Richard ** To leave the list, click on the immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=unsubscribe] ** If this link doesn't work then send a message to: ** program-l-request@xxxxxxxxxxxxx ** and in the Subject line type ** unsubscribe ** For other list commands such as vacation mode, click on the ** immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=faq] ** or send a message, to ** program-l-request@xxxxxxxxxxxxx with the Subject:- faq** To leave the list, click on the immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=unsubscribe] ** If this link doesn't work then send a message to: ** program-l-request@xxxxxxxxxxxxx ** and in the Subject line type ** unsubscribe ** For other list commands such as vacation mode, click on the ** immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=faq] ** or send a message, to ** program-l-request@xxxxxxxxxxxxx with the Subject:- faq ** To leave the list, click on the immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=unsubscribe] ** If this link doesn't work then send a message to: ** program-l-request@xxxxxxxxxxxxx ** and in the Subject line type ** unsubscribe ** For other list commands such as vacation mode, click on the ** immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=faq] ** or send a message, to ** program-l-request@xxxxxxxxxxxxx with the Subject:- faq
** To leave the list, click on the immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=unsubscribe] ** If this link doesn't work then send a message to: ** program-l-request@xxxxxxxxxxxxx ** and in the Subject line type ** unsubscribe ** For other list commands such as vacation mode, click on the ** immediately-following link:- ** [mailto:program-l-request@xxxxxxxxxxxxx?subject=faq] ** or send a message, to ** program-l-request@xxxxxxxxxxxxx with the Subject:- faq