UnboundLocalError: local variable 'cnt' referenced before assignment - python

class Solution:
def subarraysDivByK(self, A, K):
"""
:type A: List[int]
:type K: int
:rtype: int
"""
l = len(A)
div = [[0 for col in range(l)] for row in range(l)]
sums = [[None for col in range(l)] for row in range(l)]
global cnt
cnt = 0
for i in range(l):
if A[i]%K == 0:
div[i][i] = 1
cnt = cnt+1
def impl(self,st,en):
print(st,en)
if sums[st][en]!=None:
return sums[st][en]
if A[st] == A[en]:
if A[st]%K == 0:
sums[st][st] = A[st]
div[st][st] = 1
print(st,en,sums[st][en])
if sums[st][en]%k == 0:
div[st][en] = 1
cnt = cnt+1
return sums[st][st]
elif st+1==en:
sums[st][en] = A[st]+A[en]
print(st,en,sums[st][en])
if sums[st][en]%K == 0:
div[st][en] = 1
cnt = cnt+1
return sums[st][en]
else:
if sums[st+1][en]==None:
sums[st][en] = impl(self,st+1,en)+A[st]
if sums[st][en-1]==None:
sums[st][en] = impl(self,st,en-1)+A[en]
#sums[st][en] = sums[st+1][en]+ A[st]
print(st,en,sums[st][en])
if sums[st][en]%K == 0:
div[st][en] = 1
cnt = cnt+1
return sums[st][en]
impl(self,0,len(A)-1)
print(cnt)
#print(sums)

You should add global cnt inside the function impl so that the global variable will be visible.
def impl(self,st,en):
global cnt
...
For more information, please check: enter link description here.

Related

TypeError: can't multiply sequence by non-int of type 'dict'

Trying to get this code to sort topological, but I get the error mentioned in the topic. How do I solve this?
PS: I do also have a method for adding edges and variables.
def __init__(self):
self.edges = defaultdict(lambda: [])
self.variables = {}
def sorted_nodes(self):
indegree = [0]*self.variables
for i in self.edges:
for j in self.edges[i]:
indegree[j] += 1
Q = []
for i in range(self.variables):
if indegree[i] == 0:
Q.append(i)
count = []
L = []
while Q:
start = Q.pop()
L.append(start)
for i in self.edges[start]:
indegree[i] -= 1
if indegree[i] == 0:
Q.append(i)
count += 1
if count != self.variables:
return False
else:
return L

TypeError: 'NoneType' object is not iterable when implementing Perceptron, see code below

I have a problem with my perceptron codes.I receive this when I execute my code. I checked my two txt files and I am pretty sure the two of them are definitely ok. So can someone help? Thanks a lot
Traceback (most recent call last):
File "perceptron.py", line 160, in <module>
test()
File "perceptron.py", line 133, in test
w,k,i = p.perceptron_train('train.txt')
TypeError: 'NoneType' object is not iterable
Here is my code
import numpy as np
import matplotlib.pyplot as plt
class Data():
def __init__(self,x,y):
self.len = len(x)
self.x = x
self.y = y
class Perceptron():
def __init__(self,N,X):
self.w = np.array([])
self.N = N
self.X =X
def prepare_training(self,file):
file = open(file,'r').readlines()
self.dic = set([])
y = []
vocab = {}
for i in range(len(file)):
words = file[i].strip().split()
y.append(int(words[0])*2-1)
for w in set(words[1:]):
if w in vocab:
vocab[w].add(i)
if i < self.N and len(vocab[w]) >= self.X:
self.dic.add(w)
elif i < self.N:
vocab[w] = set([i])
x = np.zeros((len(file),len(self.dic)))
self.dic = list(self.dic)
for i in range(len(self.dic)):
for j in vocab[self.dic[i]]:
x[j][i] = 1
self.training = Data(x[:self.N],y[:self.N])
self.validation = Data(x[self.N:],y[self.N:])
return x,y
def update_weight(self,x,y):
self.w = self.w + x * y
def perceptron_train(self,data):
x,y = self.prepare_training(data)
self.w = np.zeros(len(self.dic),int)
passes = 0
total_passes = 100
k = 0
while passes < total_passes:
print('passes:',passes)
mistake = 0
for i in range(self.N):
check = y[i] * np.dot(self.w,x[i])
if (check == 0 and (not
np.array_equal(x[i],np.zeros(len(self.dic),int)))) or (check < 0):
self.update_weight(x[i],y[i])
mistake += 1
k += 1
passes += 1
print('mistake:',mistake)
if mistake == 0:
print('converge at pass:',passes)
print('total mistakes:', k)
return self.w, k, passes
def perceptron_error(self,w,data):
error = 0
for i in range(data.len):
if data.y[i] * np.dot(w,data.x[i]) < 0:
error += 1
return error/data.len
def test(self,report):
x = np.zeros(len(self.dic),int)
for i in range(len(self.dic)):
if self.dic[i] in report:
x[i] = 1
if np.dot(self.w,x) > 0:
return 1
else:
return 0
def perceptron_test(self,data):
test = open(data,'r').readlines()
y = []
mistake = 0
for t in test:
y0 = int(t.strip().split()[0])
report = set(t.strip().split()[1:])
r = self.test(report)
y.append(r)
if (y0 != r):
mistake += 1
return y,mistake/len(test)
def predictive_words(self):
w2d = {}
for i in range(len(self.dic)):
try:
w2d[self.w[i]].append(self.dic[i] + " ")
except:
w2d[self.w[i]] = [self.dic[i] + " "]
key = list(w2d.keys())
key.sort()
count = 0
most_positive = ""
most_negative = ""
for i in range(len(key)):
for j in range(len(w2d[key[i]])):
most_negative += w2d[key[i]][j]
count += 1
if count == 5:
break
if count == 5:
break
count = 0
for i in range(len(key)):
for j in range(len(w2d[key[len(key)-i-1]])):
most_positive += w2d[key[len(key)-i-1]][j]
count += 1
if count == 5:
break
if count == 5:
break
return most_positive,most_negative
def test():
p = Perceptron(500,30)
w,k,i = p.perceptron_train('train.txt')
print(p.perceptron_error(w,p.validation))
normal,abnormal = p.predictive_words()
print('Normal:\n',normal)
print('Abnormal:\n',abnormal)
print(p.perceptron_test('test.txt'))
def plot_error():
x = [100,200,400,500]
y = []
for n in x:
p = Perceptron(n,10)
w,k,i = p.perceptron_train('train.txt')
y.append(p.perceptron_error(w,p.validation))
plt.plot(x,y)
plt.show()
def plot_converge():
x = [100,200,400,500]
y = []
for n in x:
p = Perceptron(n,10)
w,k,i = p.perceptron_train('train.txt')
y.append(i)
plt.plot(x,y)
plt.show()
test()
perceptron_train has the implicit return value None if mistakes!=0, so that's what you're seeing here.

Python error: "global name 'counter1' is not defined"

My code:
class Persistence:
num = 0
counter1 = 0
counter2 = 0
def __init__(self, num):
self.num = num
#num = input("Enter a non-negative number:: ")
if num < 0:
raise NameError("Negative")
#test else:
#print "ok!"
num_list = []
def digitize(self, num):
num_list = []
n = str(num)
for digit in n:
num_list.append(int(digit))
return num_list
def sum_digits(self, num):
the_list = self.digitize(num)
the_sum = 0
for digit in the_list:
the_sum = the_sum + digit
return the_sum
def times_digits(self, num):
the_list = self.digitize(num)
the_product = 0
for digit in the_list:
the_product = the_product * digit
return the_product
def additive(self, num):
global counter1
sum1 = self.sum_digits(num)
list1 = []
list1 = self.digitize(sum1)
if list1.__len__() > 1:
global counter1
counter1 = counter1 + 1
self.additive(sum1)
return sum1, counter1
def multiplicative(self, num):
global counter2
prod1 = self.times_digits(num)
list1 = []
list1 = self.digitize(prod1)
if list1.__len__() > 1:
global counter1
counter2 = counter2 + 1
self.multiplicative(prod1)
return prod1, counter2
c = Persistence(5)
print c.additive(5)
print c.multiplicative(5)
Not sure why I'm getting this error? It seems to me that I have defined the global variable counter1. I'm also getting this error for counter2, and the only way I've been able to resolve the error is by inserting counter1 = 0 (or any other number) a single line above the return statement on the additive() method. Help would be much appreciated!!
One of the solutions is to move the counters out of class like:
# global variables
num = 0
counter1 = 0
counter2 = 0
class Persistence:
....
....
Leave the rest of your code unmodified.
counter1 and counter2 are defined as class attributes currently, if you want to keep it that way, just access them as classname.attrname:
class Persistence:
num = 0
counter1 = 0
counter2 = 0
def __init__(self, num):
self.num = num
#num = input("Enter a non-negative number:: ")
if num < 0:
raise NameError("Negative")
#test else:
#print "ok!"
num_list = []
def digitize(self, num):
...
def sum_digits(self, num):
...
def times_digits(self, num):
...
def additive(self, num):
sum1 = self.sum_digits(num)
list1 = []
list1 = self.digitize(sum1)
if list1.__len__() > 1:
Persistence.counter1 = Persistence.counter1 + 1
self.additive(sum1)
return sum1, Persistence.counter1
def multiplicative(self, num):
prod1 = self.times_digits(num)
list1 = []
list1 = self.digitize(prod1)
if list1.__len__() > 1:
Persistence.counter2 = Persistence.counter2 + 1
self.multiplicative(prod1)
return prod1, Persistence.counter2
c = Persistence(5)
print c.additive(5)
print c.multiplicative(5)
The appropriate way of solving this issue will be to move the 3 class variables to init method. These variable will become associated with the object can be accessed using 'self'
class Persistence(object):
def __init__(self):
self.counter1 = 0
self.counter2 = 0
def digitize(self, num):
return [int(digit) for digit in str(num)]
def sum_digits(self, num):
return sum(self.digitize(num))
def times_digits(self, num):
the_list = self.digitize(num)
the_product = 0
for digit in the_list:
the_product = the_product * digit
return the_product
def additive(self, num):
sum1 = self.sum_digits(num)
list1 = []
list1 = self.digitize(sum1)
if len(list1) > 1:
self.counter1 += 1
self.additive(sum1)
return sum1, self.counter1
def multiplicative(self, num):
prod1 = self.times_digits(num)
list1 = []
list1 = self.digitize(prod1)
if len(list1) > 1:
self.counter2 += 1
self.multiplicative(prod1)
return prod1, self.counter2
c = Persistence()
print c.additive(5)
print c.multiplicative(5)
You don't num in the constructor if you are not actually using it.

Minimum spanning tree using Kruskal in Python, recursion enters a infinite loop

The purpose of this code is to create the shortest path that connect each point. I've tried to implement the Kruskals algorithm in Python, but there is a problem and it occurs when the function findSet(x) is called. It seems like the program enters a infinite loop. I've tried to print x, x.dad and x.dad.dad and x in the crucial moment returns the initial x. I really don't know where is the problem.
class Point:
def __init__(self,x = None, y = None):
self.x = x
self.y = y
self.dad = None
self.rank = None
class Edge:
def __init__(self, firstPoint = None, secondPoint = None, value = None):
self.firstPoint = firstPoint
self.secondPoint = secondPoint
if self.firstPoint != None and self.secondPoint != None:
self.value = abs(firstPoint.x-secondPoint.x) + abs(firstPoint.y - secondPoint.y)
else:
self.value = float("inf")
def makeSet(node):
node.dad = node
node.rank = 0
def findSet(x):
print x, x.dad,x.dad.dad
if x == x.dad:
return x
x.dad = findSet(x.dad)
return x.dad
def unionSet(node1,node2):
root1 = findSet(node1)
root2 = findSet(node2)
if root1.rank < root2.rank:
root1.dad = root2
if root1.rank > root2.rank:
root2.dad = root1
else:
root2.dad = root1
root1.rank += 1
def merge(A, p, q, r):
L = A[p:q+1]
R = A[q+1:r+1]
infinite = Edge()
L.append(infinite)
R.append(infinite)
temp = []
i = 0
j = 0
for k in range(p,r+1):
if L[i].value <= R[j].value:
temp.append(L[i])
i += 1
else:
temp.append(R[j])
j += 1
A[p:r+1] = temp
def mergeSort(A,p,r):
A2 = A
if p < r:
q = int((p+r)/2)
mergeSort(A2, p, q)
mergeSort(A2, q+1, r)
merge(A2, p, q, r)
def readPoint(A):
temp = []
for i in range(0,len(A), 2):
tempPoint = Point(A[i],A[i+1])
makeSet(tempPoint)
temp.append(tempPoint)
return temp
def calculateEdges(A):
tempArray = []
for i in range(0,len(A)):
for j in range(i+1,len(A)):
edge = Edge(A[i], A[j])
tempArray.append(edge)
return tempArray
def Kruskal(N, E):
mergeSort(E,0,len(E)-1)
j = 0
i = 0
total = 0
while j < N:
if findSet(E[i].firstPoint) != findSet(E[i].secondPoint):
unionSet(E[i].firstPoint,E[i].secondPoint)
j += 1
total += E[i].value
if i < len(E) - 1:
i += 1
return total
Ar = readPoint([18, 2, 99, 68])
E = calculateEdges(Ar)
print Kruskal(len(Ar),E)

how to solve the print string error on python eclipse

I am not sure why do i get this error from the console:
<<
print stirngp[state[i][j]]
^
SyntaxError: invalid syntax
<<
Furthermore it seems that the IDE put a red close on the following code line
line = raw_input("Enter:")
I am not sure what did i do wrong, the following code is as shown below
def isTerminal(state):
stateT = zip(*state)
for i in range(3):
if all(state[i][0] == j for j in state[i]) and state[i][0] != 0:
return state[i][0]
if all(stateT[i][0] == j for j in stateT[i]) and stateT[i][0] != 0:
return stateT[i][0]
if (state[0][0] == state[1][1] == state[2][2]) or \
(state[0][2] == state[1][1] == state[2][0]):
if state[1][1] != 0:
return state[1][1]
for i in range(3):
if 0 in state[i]:
return None
return 0
def succ(state):
# print state
countX = 0
countO = 0
for i in range(3):
for j in range(3):
if state[i][j] == 1: countX = countX + 1
if state[i][j] == -1: countO = countO + 1
if countX > countO:
player = "MIN"
else:
player = "MAX"
succList = []
v = {"MIN":-1,"MAX":1}
for i in range(3):
for j in range(3):
if state[i][j] == 0:
succ = [k[:] for k in state]
succ[i][j] = v[player]
succList = succList + [succ]
# print succList
return succList
def nextplay(player):
if player == "MIN":
return "MAX"
else:
return "MIN"
def minimax(state,alpha,beta,player):
value = isTerminal(state)
if value != None:
# print "TERMINAL:", state, value, player
return value
if player == "MIN":
for y in succ(state):
beta = min(beta, minimax(y,alpha,beta,"MAX"))
if beta <= alpha: return alpha
return beta
if player == "MAX":
for y in succ(state):
alpha = max(alpha, minimax(y,alpha,beta,"MIN"))
if alpha >= beta: return beta
return alpha
def printing(state):
p = {-1:"O",0:".",1:"X"}
for i in range(3):
for j in range(3):
print p[state[i][j]],
print ""
print ""
def main():
state = [[0,0,0],
[0,0,0],
[0,0,0]]
val = isTerminal(state)
while val == None:
line = raw_input("Enter:")
x = line.split(",")
a = int(x[0]); b = int(x[1])
state[a][b] = 1
if isTerminal(state) != None:
printing(state)
return
# determine which successive state is better
succList = succ(state)
succValList = []
for i in succList:
succValList = succValList + [(minimax(i,-1,1,"MAX"),i)]
succValList.sort(key=lambda x:x[0])
state = succValList[0][1] # can also randomly choose other states of the same minimax value
printing(state)
val = isTerminal(state)
if __name__ == '__main__':
main()
As far as i know you can't use raw_input() in Python 3. It's been changed to just input()
http://docs.python.org/dev/whatsnew/3.0.html
also what is stringp? is it an existing list?
if so then state[i][j] MUST return an integer so you can retrieve the item at that index of stringp[]

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