Re: trigger at TDM/2 only
DaveA, Yep, that seems to just be about it! Much easier! Thanks for the hint! Much appreciated :) Ron On Thursday, June 6, 2013 5:43:11 PM UTC-7, Dave Angel wrote: On 06/06/2013 08:03 PM, cerr wrote: Hi, I have a process that I can trigger only at a certain time. Assume I have a TDM period of 10min, that means, I can only fire my trigger at the 5th minute of every 10min cycle i.e. at XX:05, XX:15, XX:25... For hat I came up with following algorithm which oly leaves the waiting while loop if minute % TDM/2 is 0 but not if minute % TDM is 0: min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min while not (min%tdm_timeslot != 0 ^ min%(int(tdm_timeslot/2)) != 0): You might have spent three minutes and simplified this for us. And in the process discovered the problem. (BTW, min() is a builtin function, so it's not really a good idea to be shadowing it.) You didn't give python version, so my sample is assuming Python 2.7 For your code it shouldn't matter. tdm = 10 tdm2 = 5 y = min(3,4) print y for now in range(10,32): print now, now%tdm, now%tdm2, print not(now % tdm !=0 ^ now%tdm2 !=0) #bad print not((now % tdm !=0) ^ (now%tdm2 !=0)) #good Your problem is one of operator precedence. Notice that ^ has a higher precedence than != operator, so you need the parentheses I added in the following line. What I don't understand is why you used this convoluted approach. Why not print now%tdm != tdm2 For precedence rules, see: http://docs.python.org/2/reference/expressions.html#operator-precedence -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Re: trigger at TDM/2 only
MRAB, Thanks for the hint! Yep, that's much easier! Thanks! :) Ron On Thursday, June 6, 2013 5:49:55 PM UTC-7, MRAB wrote: On 07/06/2013 01:03, cerr wrote: Hi, I have a process that I can trigger only at a certain time. Assume I have a TDM period of 10min, that means, I can only fire my trigger at the 5th minute of every 10min cycle i.e. at XX:05, XX:15, XX:25... For hat I came up with following algorithm which oly leaves the waiting while loop if minute % TDM/2 is 0 but not if minute % TDM is 0: min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min while not (min%tdm_timeslot != 0 ^ min%(int(tdm_timeslot/2)) != 0): time.sleep(10) logger.debug(WAIT +str(datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min)) logger.debug(str(min%(int(tdm_timeslot/2)))+ - +str(min%tdm_timeslot)) min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min logger.debug(RUN UPDATE CHECK...) But weird enough, the output I get is something like this: I would expect my while to exit the loop as soon as the minute turns 1435... why is it staying in? What am I doing wrong here? WAIT 1434 3 - 3 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1435 4 - 4 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1436 0 - 5 RUN UPDATE CHECK... Possibly it's due to operator precedence. The bitwise operators , | and ^ have a higher precedence than comparisons such as !=. A better condition might be: min % tdm_timeslot != tdm_timeslot // 2 or, better yet, work out how long before the next trigger time and then sleep until then. -- http://mail.python.org/mailman/listinfo/python-list
trigger at TDM/2 only
Hi, I have a process that I can trigger only at a certain time. Assume I have a TDM period of 10min, that means, I can only fire my trigger at the 5th minute of every 10min cycle i.e. at XX:05, XX:15, XX:25... For hat I came up with following algorithm which oly leaves the waiting while loop if minute % TDM/2 is 0 but not if minute % TDM is 0: min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min while not (min%tdm_timeslot != 0 ^ min%(int(tdm_timeslot/2)) != 0): time.sleep(10) logger.debug(WAIT +str(datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min)) logger.debug(str(min%(int(tdm_timeslot/2)))+ - +str(min%tdm_timeslot)) min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min logger.debug(RUN UPDATE CHECK...) But weird enough, the output I get is something like this: I would expect my while to exit the loop as soon as the minute turns 1435... why is it staying in? What am I doing wrong here? WAIT 1434 3 - 3 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1435 4 - 4 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1436 0 - 5 RUN UPDATE CHECK... Thank you for any assistance! Ron -- http://mail.python.org/mailman/listinfo/python-list
Re: trigger at TDM/2 only
On 06/06/2013 08:03 PM, cerr wrote: Hi, I have a process that I can trigger only at a certain time. Assume I have a TDM period of 10min, that means, I can only fire my trigger at the 5th minute of every 10min cycle i.e. at XX:05, XX:15, XX:25... For hat I came up with following algorithm which oly leaves the waiting while loop if minute % TDM/2 is 0 but not if minute % TDM is 0: min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min while not (min%tdm_timeslot != 0 ^ min%(int(tdm_timeslot/2)) != 0): You might have spent three minutes and simplified this for us. And in the process discovered the problem. (BTW, min() is a builtin function, so it's not really a good idea to be shadowing it.) You didn't give python version, so my sample is assuming Python 2.7 For your code it shouldn't matter. tdm = 10 tdm2 = 5 y = min(3,4) print y for now in range(10,32): print now, now%tdm, now%tdm2, print not(now % tdm !=0 ^ now%tdm2 !=0) #bad print not((now % tdm !=0) ^ (now%tdm2 !=0)) #good Your problem is one of operator precedence. Notice that ^ has a higher precedence than != operator, so you need the parentheses I added in the following line. What I don't understand is why you used this convoluted approach. Why not print now%tdm != tdm2 For precedence rules, see: http://docs.python.org/2/reference/expressions.html#operator-precedence -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Re: trigger at TDM/2 only
On 07/06/2013 01:03, cerr wrote: Hi, I have a process that I can trigger only at a certain time. Assume I have a TDM period of 10min, that means, I can only fire my trigger at the 5th minute of every 10min cycle i.e. at XX:05, XX:15, XX:25... For hat I came up with following algorithm which oly leaves the waiting while loop if minute % TDM/2 is 0 but not if minute % TDM is 0: min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min while not (min%tdm_timeslot != 0 ^ min%(int(tdm_timeslot/2)) != 0): time.sleep(10) logger.debug(WAIT +str(datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min)) logger.debug(str(min%(int(tdm_timeslot/2)))+ - +str(min%tdm_timeslot)) min = datetime.datetime.now().timetuple().tm_hour*60 + datetime.datetime.now().timetuple().tm_min logger.debug(RUN UPDATE CHECK...) But weird enough, the output I get is something like this: I would expect my while to exit the loop as soon as the minute turns 1435... why is it staying in? What am I doing wrong here? WAIT 1434 3 - 3 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1434 4 - 4 WAIT 1435 4 - 4 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1435 0 - 5 WAIT 1436 0 - 5 RUN UPDATE CHECK... Possibly it's due to operator precedence. The bitwise operators , | and ^ have a higher precedence than comparisons such as !=. A better condition might be: min % tdm_timeslot != tdm_timeslot // 2 or, better yet, work out how long before the next trigger time and then sleep until then. -- http://mail.python.org/mailman/listinfo/python-list
