How do I write this function in Python? - python

*I'm a Beginner...
My friend tried to help me a bit with this but I can't seem to solve it. I'm not really sure what to do so any help would be greatly appreciated.I get the following error in averageMPG,"name stats city is parameter and global".I also wasn't really sure how to write both functions in my readData function as you can see. The problem is in the picture. I haven't succeeded in part b so I haven't moved on,
def readData(carmodelData_city):
global stats_city,stats_hwy
infile=open("carModelData_city", 'r')
stats_city=[]
for s in infile.read.split():
stats.append(float(s))
return stats_city
def read_Data(carmodelData_hwy):
global stats_city,stats_hwy
infile=open("carModelData_hwy", 'r')
stats_hwy=[]
for s in infile.read.split():
stats.append(float(s))
return stats_hwy
def averageMPG(stats_city, stats_hwy):
global stats_city,stats_hwy
totals=sum(stats_city)
length=len(stats_city)
avg1=totals/length
print("The averge mpg city is", avg1)
totals1=sum(stats_hwy)
length1=len(stats_hwy)
avg2=totals/length
print("The average mpg highway is", avg2)
average=(avg1+avg2)/2
print("The combined averge mpg is", average)
def main():
global stats_city,stats_hwy
stats_city=readData("carModelData_city", "r")
stats_hwy=read_Data("carModelData_hwy", "r")
[enter image description here][1]main()

You named a function parameter stats_city, and also declared it a global value. Those two things are incompatible.
AFAICT, none of your code actually requires anything to be global in the first place, so stop declaring everything global, and you should be fine.
Well, fine on that specific error anyway. The massive overuse of global here feels an awful lot like cargo cult programming, and you have many other problems (e.g. infile.read.split() is going to try to split the read method of the file; you forgot parens, so it's not actually calling read to get data back). You're also returning at the end of the first iteration of each loop, when I suspect you want to finish the loops and return the accumulated values. You need to learn a lot more of the basics here; please talk to a professor or a tutor.

Also, your "stats.append()" calls should probably be "stats_city.append" in the first function and "stats_hwy.append" in the second. You will return after one iteration in each function unless you adjust your idents on the return call.

Related

i have challenges implementing OOP in python

I am facing challenges implementing OOP in python to enable me to call the functions whenever i want , so far i have no syntax errors which makes quite challenging for me . The first part of the code runs ehich is to accept data but the function part does not run.
I have tried different ways of calling the function by creating an instance of it.
print (list)
def tempcheck(self,newList):
temp=newList[0]
if temp==27:
print ("Bedroom has ideal temperature ")
elif temp>=28 or temp<=26:
print ("Bedroom Temperature is not ideal ,either too low or too cold. ")
print ("Please to adjust the temperature to the optimum temperature which is 27 degree Celsuis")
# now to initialize args
def __init__(self,temp,puri1,bedwashroom,newList):
self.temp=temp
self.puri1=puri1
self.bedwashroom=bedwashroom
tempcheck(newList)
# now calling the functions
newvalue=tempcheck(list)
# where list contains the values from the input function.
I expected the function to to check the specific value at the location in the list provided which is called list and also for the function to return a string based on the if statements.
i got it right ,i figured out an alternative to my bug thanks for the critique however any further addition is welcome,
the main goal was to create a function that takes input and passes it to list to be used later i guess this code is less cumbersome
the link to the full code is pasted below

Repeating a function with another function

for an assignment we needed to make a function that flipped a coin and another to flip it 100 times. I was able to make a function that flipped a coin, but got stuck when trying to call it a 100 times with another function. This is what I have right now:
import random
def TC():
face = random.randint(0,1)
if face == 1:
return "head"
else:
return "tail"
print TC()
def ply(flips):
for i in range(flips):
return TC()
print ply(100)
When I run it it just says 'none.' Please tell me where I am going wrong. Thank You!
Just to start, your method naming is very bad. I doubt this is how your professor is teaching you to name methods and variables. It's ugly, against Python standards and hard to read I suggest you take some time and read PEP 8 it's how python was intended to be written.
So instead of TC you should use something like flip_coin and instead of ply use something like play_coin_flip or even simply play.
Next I don't know if I'm stepping outside of what you have learned but instead of using randon.randint you can use randon.choice.
And finally, as others have said, when you return you quit any other execution in a function and return whatever variable you retrun in that statement thus nullifying any other iterations of the loop you're performing. I suggest something like the below as a better program with corrections applied to make it function as intended.
from random import choice
faces = ['head', 'tail']
def flip_coin():
face = choice(faces)
return face
def play_coin_flip(flips = 1):
for i in range(flips):
print(flip_coin)
if __name__ == "__main__":
play_coin_flip(100)

Python: Why my function returns None and then executes

So, I have a function which basically does this:
import os
import json
import requests
from openpyxl import load_workbook
def function(data):
statuslist = []
for i in range(len(data[0])):
result = performOperation(data[0][i])
if result in satisfying_results:
print("its okay")
statuslist.append("Pass")
else:
print("absolutely not okay")
statuslist.append("Fail" + result)
return statuslist
Then, I invoke the function like this (I've added error handling to check what will happen after stumbling upon the reason for me asking this question), and was actually amazed by the results, as the function returns None, and then executes:
statuslist = function(data)
print(statuslist)
try:
for i in range(len(statuslist)):
anotherFunction(i)
print("Confirmation that it is working")
except TypeError:
print("This is utterly nonsense I think")
The output of the program is then as follows:
None
This is utterly nonsense I think
its okay
its okay
its okay
absolutely not okay
its okay
There is only single return statement at the end of the function, the function is not recursive, its pretty straightforward and top-down(but parses a lot of data in the meantime).
From the output log, it appears that the function first returns None, and then is properly executed. I am puzzled, and I were unable to find any similar problems over the internet (maybe I phrase the question incorrectly).
Even if there were some inconsistency in the code, I'd still expect it to return [] instead.
After changing the initial list to statuslist = ["WTF"], the return is [].
To rule out the fact that I have modified the list in some other functions performed in the function(data), I have changed the name of the initial list several times - the results are consistently beyond my comprehension
I will be very grateful on tips in debugging the issue. Why does the function return the value first, and is executed after?
While being unable to write the code which would at the same time present what happened in my code in full spectrum, be readable, and wouldn't interfere with no security policies of the company, I have re-wrote it in a simpler form (the original code has been written while I had 3 months of programming experience), and the issue does not reproduce anymore. I guess there had be some level of nesting of functions that I have misinterpreted, and this re-written code, doing pretty much the same, correctly returns me the expected list.
Thank you everyone for your time and suggestions.
So, the answer appears to be: You do not understand your own code, make it simpler.

Why can't I get the output in Python?

def travel():
travel.s=0
travel.frate=[]
travel.tr=[]
def accomodation():
print"""specialises
1.place 1
a.hotel 1
b.hotel 2
Hotel1:ac/non ac rooms
Ac.for ac...
Noac.for non ac...."""
hd=[5000,6000]
hg=[4000,7000]
TAc=[1000]
Nac=[400]
ch5=input("Enter your choice")
fav=raw_input("ENter hotel choice")
mode=raw_input("Enter ac/no ac")
if(ch5==1):
for i in hd:
frate=hd[i]+TAc
else:
frate=hd[i]+Nac
if(ch5==2):
for i in range(0,2,1):
frate=hg[i]+TAc
else:
frate=hg[i]+Nac
accomodation()
travel()
When i run the program , i get the error as List Index out of range.but in hd and hg list,there are only two elements, so index number will be from 0 right?? Is there anything i should import?? I even gave statements like this:
travel.frate=travel.hg[i]+TAc
but it still doesn't come.Thank you for your effort.
the indentation is proper now,but the output is still not coming.
The specific issue you are encountering is caused by these lines here:
if(ch5==1):
for i in hd:
frate=hd[i]+TAc
hd[i] looks at hd[5000] and hd[6000] which will throw an IndexError.
But if you fix that, you're going to run into another error, because
frate=hd[i]+TAc
tries to add a list TAc to an integer hd[i], which is an unsupported operation. You probably need frate=hd[i]+TAc[0], or even better, make TAc a number rather than a list. This issue occurs elsewhere in your code as well.
Finally, while not causing explicit issues in your code right now, there are two other problems:
ch5=input("Enter your choice") is dangerous since input tells Python to run whatever code snippet the user enters. In this case, much safer to do ch5=int(raw_input("Enter your choice"))
for i in range(0,2,1): is really for i in range(2): - only use the starting index and jump parameters if you need to change them from their default, namely 0 and 1.
There are other issues like variable scope (you're expecting travel.frate to be modified from within accommodation, but that's not happening) and defining variables in functions like travel.frate (not invalid syntax, but definitely strange) but those are probably better addressed outside of this question.

Python Global Variable Not Working

I have an extremely long program for a Canasta game that I am writing, in it there is a variable that ends the turn of the player if it equals a certain value. However, the turn repeats itself.
I have read many different articles and posts on forums like this one, but none of these seem to work. I even have a debug system to print the value of the variable before the if statement, and the variable is the right value, but the if statement doesn't see the same value.
I can't give the entire code, as it is extremely long, but I can give the sections that use this variable. I am using Python 2.7.2 and cannot make files separate from the main file to import.
The first line of the program is:
endTurn=1
The following function is called when conditions to win the game are met, but I have not been able to test that this works because of the bug.
def winGame(player):
global endTurn
gameWinner=player
gameWinner["score"]+=100
endTurn=0
The following function is called when a move is made. The variable decide is a raw_input() variable.
def move(player,decide):
global endTurn
theMove=decide.lower()
#if player says to end turn
if theMove=="end":
#until player discards something
discarded=0
while not discarded:
displayHand(player)
#ask player for discard
discard=int(raw_input(" Enter the list number of the card you wish to discard:"))-1
#if discard ID is in player's hand length
if not discard<0 and not discard>len(player["hand"])-1:
#add card to discard pile and remove from hand
discardPile.append(player["hand"][discard])
del(player["hand"][discard])
discarded=1
debug("Before changing, endTurn is %s"%str(endTurn))
endTurn = 0
debug("After changing, endTurn is %s"%str(endTurn))
if theMove=="new book":
newBook(player)
if theMove=="add to book":
addBook(player)
Here is where the turn should be ended. turn(thePlayer) repeats the function. The debug statement shows the correct value, 0, but the if still reads a 1. The function this is in also has the global endTurn at the top.
debug("If ending turn, endTurn of %s should be 0."%str(endTurn))
if endTurn==1:
turn(thePlayer)
Any help is greatly appreciated!
EDIT: The code is available at http://labs.codecademy.com/CV9z#:workspace. I ask that anyone viewing the code does not modify it, so that other people can see the true code.
I fixed the bug. I removed the endTurn variable and instead made the function that ends the turn just do the turn of the next player. It also simplified my code a bit.
I am wondering though, is using this method of running a function inside of itself over and over and over again (without leaving) rather messy or maybe slowing down my program?
EDIT: I now realize that this answer does not exactly help with anyone else who is stuck with global variables...
The previous answer I posted was just wrong, as it was based on a misinterpretation of the namespace docs as I had read them (Thanks to TheifMaster for pointing out my error), so this is a SEVERELY EDITED ANSWER:
The problem is in the while loop that I was able to read when the link to the entire code was posted after the erroneous answer I gave earlier.
while gameWinner==0:
endTurn=1
turn(player1)
if not gameWinner==0:
endTurn=1
turn(player2)
The game can never get to player two in this loop until gameWinner!=0.
I added the entire code to my sandbox and changed it to:
while gameWinner==0:
endTurn=1
turn(player1)
if gameWinner==0: #if player1 did not win yet
endTurn=1
turn(player2)
However, the game is still buggy... No one can win! gameWinner is not changed globally by the winGame() function until you add it to the global statement as I have shown here.
def winGame(player):
global endTurn, gameWinner
gameWinner=player
gameWinner["score"]+=100
debug("gameWinner == " + str(gameWinner))
endTurn=0

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