如何操作列表中的元素？

Question

I'm making a program on python that needs to hold some info on lists and them execute mathematical operations on them. Here's a sample of my code:

VCentral = []
Atlantico=[]
Pacifico=[]
Norte=[]
Sur=[]
LVC=0
LA=0
LP=0
LN=0
LS=0
LTotal=0

def RegTemp(regcode):
    global LVC
    global LA
    global LP
    global LN
    global LS
    global LTotal
    registro=[]
    temp = int(input("Digite la temperatura: "))
    fecha=input("Digite la fecha: ")
    registro.extend((temp,fecha))
    if regcode==1:
        VCentral.extend(registro)
        LVC+=1
        LTotal+=1
    if regcode==2:
        Atlantico.extend(registro)
        LA+=1
        LTotal+=1
    if regcode==3:
        Pacifico.extend(registro)
        LP+=1
        LTotal+=1
    if regcode==4:
        Norte.extend(registro)
        LN+=1
        LTotal+=1
    if regcode==5:
        Sur.extend(registro)
        LS+=1
        LTotal+=1

And then I need to compare it's values to something else. here's another sample of the function I'm trying to implement:

def Mayor(regcode):
    if regcode==1:
         may=0
         for i in VCentral:
             if i[0]>may:
                 may=i[0]
         return may
    if regcode==2:
        may=0
        for i in Atlantico:
            if i[0]>may:
                may=i[0]
        return may
    if regcode==3:
        may=0
        for i in Pacifico:
            if i[0]>may:
                may=i[0]
        return may
    if regcode==4:
        may=0
        for i in Norte:
             if i[0]>may:
                 may=i[0]
        return may
    if regcode==5:
        may=0
        for i in Sur:
            if i[0]>may:
                 may=i[0]
        return may

If you could tell me why it throws an error at me I would appreciate it.

EDIT:

Traceback (most recent call last):
  File "D:/tarea2.py", line 212, in <module>
    Menu()
  File "D:/tarea2.py", line 199, in Menu
    print(EstadisticaZona(regcode))
  File "D:/tarea2.py", line 165, in EstadisticaZona
    print("Temperatura mayor: ",Mayor(2))
  File "D:/tarea2.py", line 102, in Mayor
    if i[0]>may:
TypeError: 'int' object is not subscriptable

Answer 1

The problem is that you are using array.extend() when you want array.append() . .extend takes an iterable and unpacks its contents and adds that to end of the list. .append takes a value and adds it to the end of the list without unpacking its contents. Since you want to add a tuple ( (temp,fecha) ) to the list (and not each item in the tuple), you should use array.append() .

EDIT

All that being said, there are a lot of places for improvement in your code. I simplified all the code you posted quite a bit and got it down to 7 lines. (It should work the same as your code, but no promises as I haven't seen your whole program.):

oceans = [[], [], [], [], []]

def RegTemp(regcode):
    temp = int(input("Digite la temperatura: "))
    fecha = input("Digite la fecha: ")
    oceans[regcode-1].append((temp,fecha))

def Mayor(regcode):
    return max(i[0] for i in oceans[regcode-1])

Good luck and happy coding!

Answer 2

The problem is you misuse the extend function. So when you do i[0] in the second function, it will be an error, since it is not list but a number.

You should check the append and extend function.