multithreading - python parallel calculations in a while loop -


i have been looking around time, haven't had luck finding example solve problem. have added example code. 1 can notice slow , 2 functions done separately.

my aim print every second latest parameter values. @ same time slow processes can calculated in background. latest value shown , when process ready value updated.

can recommend better way it? example helpful.

thanks lot.

import time  def processa(para):     # imitate slow process     time.sleep(5)     para += 2      return para  def processb(parb):     # imitate slow process     time.sleep(10)     parb += 5      return parb  # start here i, para, parb = 1, 0, 0  while true: # endless loop     print(i)     print(para)     print(parb)      time.sleep(1)     += 1      # update parameter     para = processa(para)      # update parameter b     parb = processb(parb)

i imagine should you. has benefit of being able add parallel funcitons total equal number of cores have. edits welcome. 

#import time module import time  #import appropriate multiprocessing functions multiprocessing import pool  #define functions #whatever slow function def slowfunction(x):     return somefunction(x)  #printingfunction def printingfunction(new,current,timedelay):     while new == current:         print current         time.sleep(timedelay)   #set initial value printed. #depending on function may take time.  currentvalue = slowfunction(sometemporallydynamicvairable)  #establish pool pool = pool()  while true: #endless loop      #an asynchronous function, continue     # run in background while printing operates.     newvalue = pool.apply_async(slowfunction(sometemporallydynamicvairable))      pool.apply(printingfunction(newvalue,currentvalue,1))      currentvalue = newvalue  #close pool pool.close()

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