Python Forum

I'm trying to plot the results, but I get this error:

Error:
NameError: name 'total_wait' is not defined.

I am able to print the result but unable to get the value in my graph.
May I know where I did it wrong?

import numpy as np

class Simulation:

   def generate_interarrival(self):
       return np.random.poisson(1./3)

   def generate_service(self):
       return np.random.poisson(1./4)  


   def __init__(self):
       self.queue = []
       self.averageWaitingTime=[]
       self.total_wait=[]

       self.num_in_system = 0

       self.clock = 0.0
       self.t_arrival = self.generate_interarrival()
       self.t_depart = float('inf')

       self.num_arrivals = 0
       self.num_departs = 0
       self.total_wait = 0.0
       self.averageWaitingTime= 0.0       


   def advance_time(self):
       t_event =min(self.t_arrival, self.t_depart)
       self.total_wait += self.num_in_system*(t_event - self.clock)  

       print self.total_wait, 'customer total wait' 



       self.clock = t_event


       if self.t_arrival <=self.t_depart:
           self.handle_arrival_event()
       else:
          self.handle_depart_event()
          self.averageWaitingTime =self.total_wait/self.t_depart
          print  self.averageWaitingTime, ' average waiting time per customer'    


   def handle_arrival_event(self ):
       self.num_in_system +=1
       self.num_arrivals += 1

       num_arrivals = self.clock+ self.generate_interarrival() 
       print num_arrivals, ' customer {} interarrival'.format(i)



       if self.num_in_system <=1:
               self.t_depart = self.clock + self.generate_service()        
       self.t_arrival = self.clock + self.generate_interarrival()


   def handle_depart_event(self):
       self.num_in_system -=1
       self.num_departs += 1        
       num_departs = self.clock 
       print num_departs, ' customer {} departed'.format(i)


       if self.num_in_system>0:
           self.t_depart = self.clock + self.generate_service()
       else:
          self.t_depart = float(' inf')


np.random.seed(0)
s = Simulation()
for i in range (1000):
   s.advance_time()    

import matplotlib.pyplot as plt
plt.plot(total_wait)
plt.ylabel('Waiting time(min)')
plt.xlabel('Number of Customers')

Quote:plt.plot(total_wait)

total_plot doesnt exist, but there is a class attribute for Simulation
s is your Simulation object in which has an attribute total_wait. Within a class definition you use self.total_wait, outside of the class you need to refer to it using the object, in this case 's'

Quote:s = Simulation()

try this....

plt.plot(s.total_wait)

I have try that but it's not working. I don't why

(Jun-04-2017, 05:43 PM)carla Wrote: [ -> ]but it's not working

in what way? Do you get another error? Post all errors in full