python help! 2

[Bryan 2760]

infile = open("partslist.txt","r")
dinner = 0
lodge = 0
line = infile.readline()
while line != "":
    partslist = line.split(";")
    category = partslist[1]
    amount = partslist[2]
    if category == "dinner":
        totalDinner = totalDinner + amount
    if category == "Lodging":
        totalLodging = totalLodging + amount
    line = infile.readline()
print ("Dinner:",totalDinner)
print ("Lodging:",totalLodging)
infile.close()
 

 

 

can someone tell me why its telling me that totalLodging is not define? Thank you

[straight_stewie]

Because the first time you declare totalLodging you define it as itself. Or in other words, you're defining an undefined variable with an undefined variable.

 

totalLodging must be defined before it is used.

In laymens terms, you must assign a concrete value to totalLodging before you use it.

 

In programming, declaring means to say that something exists.

int myInteger; // this is a declaration. It sets aside memory to hold an integer and stores the handle in myInteger

 

defining means to give something a value:

myInteger = 0; // myInteger is now defined. That is, it has a value.

 

[minibois]

Please, please please, use the Code tags next time you post code:

https://linustechtips.com/main/announcement/12-please-use-code-tags/

 

Anyways, see what you're doing above with dinner, lodge and line?

dinner = 0
lodge = 0
line = infile.readline()

This is defining a variable; which you are not doing with totalLodging.

When you say:

totalLodging = totalLodging + amount

You're basically saying "add this non existing thing and amount together", python doesn't know totalLodging yet, so it doesn't know what you want to do with it.

[Bryan 2760]

Just now, straight_stewie said:

Because the first time you declare totalLodging you define it as itself. Or in other words, you're defining an undefined variable with an undefined variable.

 

totalLodging must be defined before it is used.

In laymens terms, you must assign a concrete value to totalLodging before you use it.

 

In programming, declaring means to say that something exists.

int myInteger; // this is a declaration. It sets aside memory to hold an integer and stores the handle in myInteger

 

defining means to give something a value:

myInteger = 0; // myInteger is now defined. That is, it has a value.

 

how come i didnt have problem with the totalDinner then? it skip it and told me the total lodging is wrong? 

[straight_stewie]

1 minute ago, Bryan 2760 said:

how come i didnt have problem with the totalDinner then? it skip it and told me the total lodging is wrong? 

That's an artifact of the lexical analysis algorithm that python uses. It just noticed totalLodging first. If you fix that, you will then get the same error for totalDinner.

[Bryan 2760]

27 minutes ago, Minibois said:

Please, please please, use the Code tags next time you post code:

https://linustechtips.com/main/announcement/12-please-use-code-tags/

 

Anyways, see what you're doing above with dinner, lodge and line?

dinner = 0
lodge = 0
line = infile.readline()

This is defining a variable; which you are not doing with totalLodging.

When you say:

totalLodging = totalLodging + amount

You're basically saying "add amount and this non existing thing together", python doesn't know totalLodging yet, so it doesn't know what you want to do with it.

infile = open("partslist.txt","r")
totalDinner = 0
totalLodging = 0
line = infile.readline()
while line != "":
    partslist = line.split(";")
    category = partslist[1]
    amount = partslist[2]
    if category == "dinner":
        totalDinner = totalDinner + amount
    if category == "Lodging":
        totalLodging = totalLodging + amount
    line = infile.readline()
print ("Dinner:",totalDinner)
print ("Lodging:",totalLodging)
infile.close()

ok so i did it like this and now its saying 

Traceback (most recent call last):
  File "C:/Users/Bryan/Desktop/hw 3 # 3.py", line 12, in <module>
    totalLodging = totalLodging + amount
TypeError: unsupported operand type(s) for +: 'int' and 'str'

[Bryan 2760]

1 minute ago, Bryan 2760 said:

infile = open("partslist.txt","r")
totalDinner = 0
totalLodging = 0
line = infile.readline()
while line != "":
    partslist = line.split(";")
    category = partslist[1]
    amount = partslist[2]
    if category == "dinner":
        totalDinner = totalDinner + amount
    if category == "Lodging":
        totalLodging = totalLodging + amount
    line = infile.readline()
print ("Dinner:",totalDinner)
print ("Lodging:",totalLodging)
infile.close()

ok so i did it like this and now its saying 

Traceback (most recent call last):
  File "C:/Users/Bryan/Desktop/hw 3 # 3.py", line 12, in <module>
    totalLodging = totalLodging + amount
TypeError: unsupported operand type(s) for +: 'int' and 'str'

wait jk i think i fixed the totallodging now its giving me problems for totaldinner

[minibois]

1 minute ago, Bryan 2760 said:

infile = open("partslist.txt","r")
totalDinner = 0
totalLodging = 0
line = infile.readline()
while line != "":
    partslist = line.split(";")
    category = partslist[1]
    amount = partslist[2]
    if category == "dinner":
        totalDinner = totalDinner + amount
    if category == "Lodging":
        totalLodging = totalLodging + amount
    line = infile.readline()
print ("Dinner:",totalDinner)
print ("Lodging:",totalLodging)
infile.close()

ok so i did it like this and now its saying 

Traceback (most recent call last):
  File "C:/Users/Bryan/Desktop/hw 3 # 3.py", line 12, in <module>
    totalLodging = totalLodging + amount
TypeError: unsupported operand type(s) for +: 'int' and 'str'

int = a number (with no decimals)

str = string = characters (like words, sentences, numbers, etc.)

 

python is saying you can't add the two together, because you can't add a number and a character together.

Depending on what you want to do (and  what kind of character it is), you have two options:

 

1. "amount is a number, I want to add the two numbers together"

You have to convert amount to an int: https://guide.freecodecamp.org/python/how-to-convert-strings-into-integers-in-python/

Now they an be added together.

 

2. "amount is a character, I want to display these two words together."

you can do something like this:

totalDinner + "" + amount

This will basically tell python you dont want to add them together as a calculation; but rather just want to show these two separately as a string of characters.

3 minutes ago, Bryan 2760 said:

wait jk i think i fixed the totallodging now its giving me problems for totaldinner

What I said above applies  to totalDinner I believe

[Bryan 2760]

34 minutes ago, Minibois said:

int = a number (with no decimals)

str = string = characters (like words, sentences, numbers, etc.)

 

python is saying you can't add the two together, because you can't add a number and a character together.

Depending on what you want to do (and  what kind of character it is), you have two options:

 

1. "amount is a number, I want to add the two numbers together"

You have to convert amount to an int: https://guide.freecodecamp.org/python/how-to-convert-strings-into-integers-in-python/

Now they an be added together.

 

2. "amount is a character, I want to display these two words together."

you can do something like this:

totalDinner + "" + amount

This will basically tell python you dont want to add them together as a calculation; but rather just want to show these two separately as a string of characters.

What I said above applies  to totalDinner I believe

omg thank you so much! it works