How to reset counter (global variable) when one of the conditions changes. Basically, increase the counter by 1 until "type_name" is "Bar" if it changes to something else set the counter to 0. How can this be achieved for multiple type_names'. Thank you.
type_name = "bar"
counter = 0
class Foo(object):
"""
if type is different in the argument, reset counter to 0.
Otherwise, increment the counter by 1.
"""
def __init__(self, type_name):
self.type_name = type_name
self.counter = counter
self.reset()
def increament_counter(self):
self.counter +=1
def reset(self):
if self.type_name != type_name:
self.counter = 0
b = Foo("bar")
b.increament_counter()
b.increament_counter()
print b.counter
print "==============================="
c = Foo("taste")
c.reset()
print c.counter
c.increament_counter()
print c.counter
print "--------------------------"
d = Foo("bar")
d.increament_counter()
d.increament_counter()
print d.counter
print "--------------------------"
e = Foo("car")
e.increament_counter()
e.increament_counter()
print e.counter
What you are doing here is that you're not modifying the global variable, but you're modifying the counter in the class (self.counter)
What you need to do is, in your reset function, change the global count, and not the one in that's a property of the class object.
def reset(self):
global counter
if self.type_name != type_name:
counter = 0
Thank you. Due to space limitation I am adding updated code here with one more use case.
type_name = "bar"
counter = 1
class Foo(object):
"""
if type is different in the argument, reset counter to 0.
Otherwise increament counter by 1.
"""
def __init__(self, type_name):
self.type_name = type_name
self.counter = counter
self.reset()
def reset(self):
global counter
if self.type_name != type_name:
counter = 1
else:
counter += 1
c = Foo("taste")
print c.counter
print "--------------------------"
d = Foo("bar")
print d.counter
print "--------------------------"
e = Foo("taste")
print e.counter
print "--------------------------"
new_instances = []
for i in range(0, 10):
new_instances.append(Foo("bar"))
print new_instances
print new_instances[0].counter
print new_instances[8].counter
Related
here is some code. I want to make an if statement but only when a variable has increased
while True:
a += 1
if a ????
print('a has changed')
Here is an option.
while True:
previous = a
# do stuff
a += 1
if a != previous:
print('a has changed')
Here is a way you can do this:
while True:
old_a = a #Create a variable for the old value of a
a += 1
if a > old_a: #Check the condition if value of a has increased.
print('a has changed')
A more clever way using the python Observer pattern.
class observe_value_change():
def __init__(self):
self._initial = 1
#property
def position(self):
return self._initial
#position.setter
def position(self, new_value):
self._initial = new_value
print("execute more code here!")
print(self._initial)
To test
p = observe_value_change()
print(p.position)
p.position = 4
Explanation:
When the value of position changes, it will call the position setter method otherwise it will not be called.
So, the if block can be written inside the position setter method.
Consider this piece of code, wondering would it be possible to return a value before it gets updated.
class A:
def __init__(self):
self.n = 0
def get_next(self):
return self.n++ # Return its current value. after it gets returned, update n.
a = A()
a.get_next() # return 0
a.get_next() # return 1
This'll work:
def get_next(self):
old_value = self.n
self.n += 1
return old_value
I'm trying to create two subclasses based on the same parent class, so that they each have their own versions of the same variables defined in the parent object. However I realized that changing these variables in one of these subclasses will cause the versions in the other subclass to change as well. I know I am probably not fully understanding the idea of Inheritance. Please help!
import random
class PlayerParent():
id = 1
# Cooperate: True; Betrayal: False
opponent_moves_history = {}
self_moves_history = {}
def append_opponent_history(self, round_num, c_true, misunderstand=0.0):
# randomly change the result based on probability given in misunderstand
random_num = random.uniform(0, 1)
if random_num <= misunderstand:
c_true = not c_true
self.opponent_moves_history[round_num] = c_true
def append_self_history(self, round_num, c_true, misunderstand=0.0):
# randomly change the result based on probability given in misunderstand
random_num = random.uniform(0, 1)
if random_num <= misunderstand:
c_true = not c_true
self.self_moves_history[round_num] = c_true
score = int(0)
def score_keeper(self, round_num):
if (self.opponent_moves_history[round_num] == True) and (self.self_moves_history[round_num] == False):
self.score += 7
if (self.opponent_moves_history[round_num] == True) and (self.self_moves_history[round_num] == True):
self.score += 5
if (self.opponent_moves_history[round_num] == False) and (self.self_moves_history[round_num] == True):
self.score += 1
if (self.opponent_moves_history[round_num] == False) and (self.self_moves_history[round_num] == False):
self.score += 2
def get_score(self):
return self.score
class TitForTat(PlayerParent):
def rule(self, round_num):
if len(self.opponent_moves_history) == 0:
return True
else:
return self.opponent_moves_history[round_num - 1]
class Random(PlayerParent):
def rule(self, round_num):
random_num = random.uniform(0, 1)
if random_num >= 0.5:
return True
else:
return False
Random = Random()
Random.id = 1
TitForTat = TitForTat()
TitForTat.id = 2
def match(a, b):
game_counter = 1
# while game_counter <= 10:
#a_result = a.rule(game_counter)
# b_result = b.rule(game_counter)
# print(a_result, b_result)
# a.append_self_history(game_counter, a_result)
# b.append_opponent_history(game_counter, a_result)
# b.append_self_history(game_counter, b_result)
# a.append_opponent_history(game_counter, b_result)
# a.score_keeper(game_counter)
# b.score_keeper(game_counter)
# game_counter += 1
# print(a.get_score(), b.get_score())
a.self_moves_history[1] = True
print(a.self_moves_history, '\n', b.self_moves_history)
match(Random, TitForTat)
Resulting a.self_moves_history and b.self_moves_history is identical even though no alteration has been done to the b class variable.
I commented out chunks of the codes just to test where went wrong.
You are making opponent_moves_history a class variable, so naturally any change to it is class-wide.
In your case you should make opponent_moves_history, along with self_moves_history and id instance variables instead, so that changes made to them are specific to the instances.
class PlayerParent():
def __init__(self):
self.id = 1
self.opponent_moves_history = {}
self.self_moves_history = {}
the entire counter list of methods in side counter class do not work. I want setcap to set of cap, and check cap to see if each counter have reached their limit as hr min sec are what a clock should know i would like to initialize them inside the clock.
import time
class counter():
count = 0
cap = 0
def _init_(self):pass
def reset(self):
self.count = 0
def increment(self):
self.count += 1
def setcap(self,x):
print x
self.cap = x
def checkcap(self):
if self.cap > self.count:
return False
else:
return True
class clock():
_hr = counter()
_min = counter()
_sec = counter()
def _init_(self):
self._hr.setcap(23)
self._min.setcap(59)
self._sec.setcap(59)
def manualreset(self):
self._hr.reset()
self._min.reset()
self_sec.reset()
def tick(self):
if self._sec.checkcap():
self._sec.reset()
self._min.increment()
if self._min.checkcap():
self._min.reset()
self._hr.increment()
if self._hr.checkcap():
self._hr.reset()
else:
self._sec.increment()
newClock = clock()
raw_input("Press enter to start clock")
while newClock._hr != 24:
newClock.tick()
print str(newClock._hr.count).zfill(2) + str(newClock._min.count).zfill(2) + str(newClock._sec.count).zfill(2)
One of the problems in your code is that your init functions are init.
Try using
def __init__(self):
pass
This should solve one of your problems
My basic idea was to create a linked list, and as each new value comes in, add 1/N times the new value and subtract 1/N times the first value, then move the pointer to first along by one and free the memory that had been associated with first.
This won't ultimately be implemented in Python but just to get the process clear in my head, I tried to write it in Python, but my implementation is flawed. Do I need a doubly linked list for this? Is there an alternative approach (not linked-list based) that would be better?
Here's my attempt so far:
class Link:
def __init__(self,val):
self.next = None
self.value = val
class LinkedList:
def __init__(self,maxlength):
self.current_link = None
self.maxlength = maxlength
self.sum = 0.
self.average = None
self.length = 0
self._first_link = None
def add_link(self,val):
new_link = Link(val)
new_link.next = self.current_link
self.current_link = new_link
if self._first_link is None:
self._first_link = self.current_link
self.sum += val
if self.length < self.maxlength:
self.length += 1
else:
self.sum -= self._first_link.value
self._first_link = self._first_link.next # this line is flawed
self.average = self.sum/self.length
def get_first(self):
return self._first_link.value
# Main
ll = LinkedList(5)
for ii in xrange(10):
ll.add_link(ii)
print ii,ll.get_first(),ll.average
The problem is that _first_link gets set to a value that doesn’t have a next. That is, _first_link gets set to the first item that's added, but its next is None, so I don't see how to move it along by 1 as I want to. This is what makes me wonder if a doubly linked list is needed.
I'd appreciate any advice.
I think the simplest implementation is to use a circular linked list (a.k.a. a ring):
class Link(object):
def __init__(self, value=0.0):
self.next = None
self.value = value
class LinkedRing(object):
def __init__(self, length):
self.sum = 0.0
self.length = length
self.current = Link()
# Initialize all the nodes:
last = self.current
for i in xrange(length-1): # one link is already created
last.next = Link()
last = last.next
last.next = self.current # close the ring
def add_val(self, val):
self.sum -= current.value
self.sum += val
self.current.value = val
self.current = self.current.next
def average(self):
return self.sum / self.length
# Test example:
rolling_sum = LinkedRing(5)
while True:
x = float(raw_input())
rolling_sum.add_val(x)
print(">> Average: %f" % rolling_sum.average())
You can implement this using collections.deque and the numerically stable math for maintaining running averages:
import collections
class AveragingBuffer(object):
def __init__(self, maxlen):
assert( maxlen>1)
self.q=collections.deque(maxlen=maxlen)
self.xbar=0.0
def append(self, x):
if len(self.q)==self.q.maxlen:
# remove first item, update running average
d=self.q.popleft()
self.xbar=self.xbar+(self.xbar-d)/float(len(self.q))
# append new item, update running average
self.q.append(x)
self.xbar=self.xbar+(x-self.xbar)/float(len(self.q))
if __name__=="__main__":
import scipy
ab=AveragingBuffer(10)
for i in xrange(32):
ab.append(scipy.rand())
print ab.xbar, scipy.average(ab.q), len(ab.q)
Okay, I thought of a solution that works in O[1] time. I'm still curious if anyone has a linked-list-based solution, but this solution avoids the LL entirely:
class Recent:
def __init__(self,maxlength):
self.maxlength = maxlength
self.length = 0
self.values = [0 for ii in xrange(maxlength)]
self.index = 0
self.total = 0.
self.average = 0.
def add_val(self,val):
last = self.values[self.index%self.maxlength]
self.values[self.index%self.maxlength] = val
self.total += val
self.total -= last
if self.length < self.maxlength:
self.length += 1
self.average = self.total / self.length
self.index += 1
def print_vals(self):
print ""
for ii in xrange(self.length):
print ii,self.values[ii%self.maxlength]
print "average:",self.average
# Example to show it works
rr = Recent(5)
for ii in xrange(3):
rr.add_val(ii)
rr.print_vals()
for ii in xrange(13):
rr.add_val(ii)
rr.print_vals()