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if statement wont take variable 'a' and 'b' when declared in python if statement

I have been curious about how to simplify my work. But for now, my
problem is how to pass variables through functions and to get this If
statement to work. The variable a and b need to pass into the if
statement to check if the string is in the array 'colors' or
'other_colors'
import random;
hot_spot=0;
colors = ['R','G','B','O','P']
other_colors =['RED','GREEN','BLUE','ORANGE','PURPLE']
guesser_array=[]
def code_maker():
code_maker_array=[]
for i in range(4):
ran = random.randint(0,4)
print (ran)
code_maker_array.append(colors[ran])
print(code_maker_array)
return code_maker_array
x = code_maker()
def code_breaker():
trys = 0;
cbi = input('please put in r,g,b,o,p or red,green,blue,orange,purple_ ')
cbi = cbi.upper()
if ( isinstance(cbi,str) == True):
print ('it is a string')
print (cbi)
for i in range(4):
if (len(cbi)>=3):
a = other_colors[i].find(cbi)
else:
b = colors[i].find(cbi)
if (a >= 0 or b >= 0):
print ('yummmeiabui aebfiahfu dsdsde')
y = code_breaker()
"""
def code_checker(x):
print (x)
code_checker(x)
"""

Try this:
import random
hot_spot=0
colors = ['R','G','B','O','P']
other_colors =['RED','GREEN','BLUE','ORANGE','PURPLE']
guesser_array=[]
def code_maker():
code_maker_array=[]
for i in range(4):
ran = random.randint(0,4)
print (ran)
code_maker_array.append(colors[ran])
print(code_maker_array)
return code_maker_array
x = code_maker()
def code_breaker():
trys = 0;
cbi = input('please put in r,g,b,o,p or red,green,blue,orange,purple_ ')
cbi = cbi.upper()
if ( isinstance(cbi,str) == True):
print ('it is a string')
print (cbi)
for i in range(4):
a=b=0 #This line added
if (len(cbi)>=3):
a = other_colors[i].find(cbi)
else:
b = colors[i].find(cbi)
if (a >= 0 or b >= 0):
print ('yummmeiabui aebfiahfu dsdsde')
y = code_breaker()
"""
def code_checker(x):
print (x)
code_checker(x)
"""
The variables a and b you have defined run out of scope as soon as their respective if blocks end. To prevent this, you can simply define them by initializing them to 0 (or any other value) outside of the if statement.
While Lucefer's answer simplified code a lot, I added this because defining variables in an outer scope like this is and modifying their values later on (in the if blocks in your case) is a very common practice, you might find it helpful somewhere else as well.

remove this whole code segment
for i in range(4):
if (len(cbi)>=3):
a = other_colors[i].find(cbi)
else:
b = colors[i].find(cbi)
if (a >= 0 or b >= 0):
print ('yummmeiabui aebfiahfu dsdsde')
just simply add
if( (cbi in other_colors) or (cbi in colors) ):
print ('yummmeiabui aebfiahfu dsdsde')

Python: Failing to break out of while loop with "SyntaxError: 'break' outside loop"

I am developing a breadth-first-search algorithm for a factorization problem and am running into an interesting/confusing bug when attempting to break out of a while loop. If you run the code below, it will fail inside the "construct_path" method, stating :
File "main.py", line 96
break
SyntaxError: 'break' outside loop
but I am inside of a while loop! If anyone could give me some advice on this issue, I would really appreciate it. Thanks in advance.
from numpy import random
import itertools
import Queue
#Finding multiples, BFS problem
#Given input of list with unique integers 0 - 9 and n = range(0,1000000), calculate smallest multiple of n and unique combination of values in the list
#Example : Input : list = {0,1,2} , n = 3,
# output = 12
# Input : list = {0,1,2} , n = 50
# Output = 200
class Problem:
def __init__(self):
self.n = random.randint(0,10000000)
listSize = random.randint(1,9)
mainSet = set()
self.mainList = []
while True:
toAdd = random.randint(0,9)
if(toAdd not in self.mainList):
self.mainList.append(toAdd)
if(len(self.mainList) == listSize):
break
def get_start_state(self):
s = ''.join(map(str, self.mainList))
return int(s)
def is_goal(self, state):
return True
def get_sucessors(self):
print "Getting successors"
def breadth_first_search(problem):
# a FIFO open_set
open_set = Queue.Queue()
# an empty set to maintain visited nodes
closed_set = set()
# a dictionary to maintain meta information (used for path formation)
meta = dict() # key -> (parent state, action to reach child)
# initialize
start = problem.get_start_state()
meta[start] = (None, None)
open_set.put(start)
while not open_set.empty():
parent_state = open_set.get()
print "{} {}".format("parent_state is ", parent_state)
if problem.is_goal(parent_state):
return construct_path(parent_state, meta)
for (child_state, action) in problem.get_successors(parent_state):
if child_state in closed_set:
continue
if child_state not in open_set:
meta[child_state] = (parent_state, action)
open_set.put(child_state)
closed_set.add(parent_state)
#collect path to desired answer
def construct_path(state, meta):
action_list = list()
while True:
row = meta[state]
if (len(row) == 2):
state = row[0]
action = row[1]
action_list.append(action)
else:
break
return action_list.reverse()
x = Problem()
breadth_first_search(x)

Could be that you have a mix of tabs and spaces so that the break in line 96 looks like it is indented to be below action_list.append(action) but effectively it is below the while. That would explain the error at least.
It is just a guess. But it could be like this, using a visible tabwidth of 4 in the editor:
→ while True:
→ → row = meta[state]
if (len(row) == 2):
state = row[0]
action = row[1]
action_list.append(action)
else:
break
To the Python interpreter this looks like this (because it assumes a tabwidth of 8):
→ while True:
→ → row = meta[state]
if (len(row) == 2):
state = row[0]
action = row[1]
action_list.append(action)
else:
break
This is still valid but obviously means a different thing and would put your break outside of the while loop.

Python splitting code into functions [duplicate]

This question already has answers here:
Using global variables in a function
(25 answers)
Parameter vs Argument Python [duplicate]
(4 answers)
Closed 5 years ago.
Sorry about the length of this but I figured more info is better than not enough!!
I'm trying to split the (working) piece of Python code into functions to make it clearer / easier to use but am coming unstuck as soon as i move stuff into functions. It's basically a password generator which tries to only output a password to the user once the password qualifies as having a character from all 4 categories in it. (Lowercase, uppercase, numbers and symbols).
import random
import string
lowerasciis = string.ascii_letters[0:26]
upperasciis = string.ascii_letters[26:]
numberedstrings = str(1234567809)
symbols = "!#$%^&*()[]"
password_length = int(raw_input("Please enter a password length: "))
while True:
lowerasscii_score = 0
upperascii_score = 0
numberedstring_score = 0
symbol_score = 0
password_as_list = []
while len(password_as_list) < password_length:
char = random.choice(lowerasciis+upperasciis+numberedstrings+symbols)
password_as_list.append(char)
for x in password_as_list:
if x in lowerasciis:
lowerasscii_score +=1
elif x in upperasciis:
upperascii_score +=1
elif x in numberedstrings:
numberedstring_score +=1
elif x in symbols:
symbol_score +=1
# a check for the screen. Each cycle of the loop should display a new score:
print lowerasscii_score, upperascii_score, numberedstring_score, symbol_score
if lowerasscii_score >= 1 and upperascii_score >= 1 and numberedstring_score >= 1 and symbol_score >=1:
password = "".join(password_as_list)
print password
break
And here is my attempt at splitting it. When i try to run the below it complains of "UnboundLocalError: local variable 'upperascii_score' referenced before assignment" in the scorepassword_as_a_list() function
import random
import string
lowerasciis = string.ascii_letters[0:26]
upperasciis = string.ascii_letters[26:]
numberedstrings = str(1234567809)
symbols = "!#$%^&*()[]"
password_length = int(raw_input("Please enter a password length: "))
lowerasscii_score = 0
upperascii_score = 0
numberedstring_score = 0
symbol_score = 0
password_as_list = []
def genpassword_as_a_list():
while len(password_as_list) < password_length:
char = random.choice(lowerasciis+upperasciis+numberedstrings+symbols)
password_as_list.append(char)
def scorepassword_as_a_list():
for x in password_as_list:
if x in lowerasciis:
lowerasscii_score +=1
elif x in upperasciis:
upperascii_score +=1
elif x in numberedstrings:
numberedstring_score +=1
elif x in symbols:
symbol_score +=1
# give user feedback about password's score in 4 categories
print lowerasscii_score, upperascii_score, numberedstring_score, symbol_score
def checkscore():
if lowerasscii_score >= 1 and upperascii_score >= 1 and numberedstring_score >= 1 and symbol_score >=1:
return 1
else:
return 0
def join_and_printpassword():
password = "".join(password_as_list)
print password
while True:
genpassword_as_a_list()
scorepassword_as_a_list()
if checkscore() == 1:
join_and_printpassword()
break

The primary issue here is that you need to keep track of the scope of the various variables that you're using. In general, one of the advantages of splitting your code into functions (if done properly) is that you can reuse code without worrying about whether any initial states have been modified somewhere else. To be concrete, in your particular example, even if you got things working right (using global variables), every time you called one of your functions, you'd have to worry that e.g. lowerassci_score was not getting reset to 0.
Instead, you should accept anything that your function needs to run as parameters and output some return value, without manipulating global variables. In general, this idea is known as "avoiding side-effects." Here is your example re-written with this in mind:
import random
import string
lowerasciis = string.ascii_letters[0:26]
upperasciis = string.ascii_letters[26:]
numberedstrings = str(1234567809)
symbols = "!#$%^&*()[]"
def genpassword_as_a_list(password_length):
password_as_list = []
while len(password_as_list) < password_length:
char = random.choice(lowerasciis+upperasciis+numberedstrings+symbols)
password_as_list.append(char)
return password_as_list
def scorepassword_as_a_list(password_as_list):
lowerasscii_score = 0
upperascii_score = 0
numberedstring_score = 0
symbol_score = 0
for x in password_as_list:
if x in lowerasciis:
lowerasscii_score +=1
elif x in upperasciis:
upperascii_score +=1
elif x in numberedstrings:
numberedstring_score +=1
elif x in symbols:
symbol_score +=1
# give user feedback about password's score in 4 categories
return (
lowerasscii_score, upperascii_score, numberedstring_score,
symbol_score
)
def checkscore(
lowerasscii_score, upperascii_score, numberedstring_score,
symbol_score):
if lowerasscii_score >= 1 and upperascii_score >= 1 and numberedstring_score >= 1 and symbol_score >=1:
return 1
else:
return 0
def join_and_printpassword(password_as_list):
password = "".join(password_as_list)
print password
password_length = int(raw_input("Please enter a password length: "))
while True:
password_list = genpassword_as_a_list(password_length)
current_score = scorepassword_as_a_list(password_list)
if checkscore(*current_score) == 1:
join_and_printpassword(password_list)
break
A few notes on this:
Notice that the "score" variables are introduced inside the scorepassword_as_list function and (based on the scoping rules) are local to that function. We get them out of the function by passing them out as a return value.
I've used just a bit of magic near the end with *current_score. Here, the asterisk is used as the "splat" or "unpack" operator. I could just as easily have written checkscore(current_score[0], current_score[1], current_score[2], current_score[3]); they mean the same thing.
It would probably be useful to read up a bit more on variable scoping and namespaces in Python. Here's one guide, but there may be better ones out there.

Function based on conditions will not return value- python

I am new to this, and I am looking for help. I currently am stuck in a program I'm trying to complete. Here it is:
def searchStock(stockList, stockPrice, s):
for i in range(len(stockList)):
if s == stockList[i]:
s = stockPrice[i]
elif s != stockList[i]:
s = -1
return s
def mainFun():
stockList= []
stockPrice = []
l = 1
while l > 0:
stocks = str(input("Enter the name of the stock:"))
stockList += [stocks]
if stocks == "done"or stocks == 'done':
l = l * -1
stockList.remove("done")
else:
price = int(input("Enter the price of the stock:"))
stockPrice += [price]
l = l + 1
print(stockList)
print(stockPrice)
s = input("Enter the name of the stock you're looking for:")
s = searchStock(stockList, stockPrice, s)
Every time I run the program to the end, it never returns the variable s for some reason. If i replace return with print, it always prints -1 instead of the stockPrice if its on the list. I cant seem to get it to work. Can someone please help me?

Try adding this print to help you debug:
def searchStock(stockList, stockPrice, s):
output = -1
for i in range(len(stockList)):
if s == stockList[i]:
output = stockPrice[i]
print i, output, stockList[i], stockPrice[i]
elif s != stockList[i]:
output = -1
return output
Also I changed one of your variables, it seems better than modifying your input value and then returning it.

"None" included in program output... why?

i've searched the forum and found similar questions, but no luck in solving my problem.
My code is designed to swap every two letters of each word using recursion and print the result. For words with an even amount of letters, the word "None" is included in the output and i don't know how to fix...
here's the code:
def encryptLine(line, count):
headline = line[count:]
if length(headline) > 0:
if count == length(line) - 1:
new = headline
return new
elif count <= length(line):
new = head(tail(headline)) + head(headline)
new = new + str(encryptLine(line, count+2))
return new
print(encryptLine('abcd', 0))
the output for 'abcd' is badcNone, which is correct except for the word None. the output for 'abcde' is 'badce', which is correct...
thanks in advance for your help!

Add return "" to the function definition, that is
def encryptLine(line, count):
headline = line[count:]
if length(headline) > 0:
if count == length(line) - 1:
new = headline
return new
elif count <= length(line):
new = head(tail(headline)) + head(headline)
new = new + str(encryptLine(line, count+2))
return new
return ""
Otherwise, the function will return None if length(headline) > 0 does not hold.

None is here because your function return nothing.
There is 1 case where you return nothing it is
if length(headline) <= 0:
In Python, if there is no return to a function and you try to access to a return value, the value will be None.