I have the following list:
lista = [ 'A','B','C','D']
I want to count the number of elements to a certain point, I know that if you do len(lista) it will count all the elements but what I want is for example until C it will give me the number 3.
Just take the index and add it with 1 more, since the first index is 0.
lista = ['A','B','C','D']
print lista.index('C') + 1;
To get the array index use the "index" method.
You can use the index to find the position of the desired element and calculate the quantity discounting from the total elements, for example:
lista = [ 'A','B','C','D']
indice = lista.index('C')
(indice + 1)
Another way would be to use for, as Wictor proposed in the comments:
i = 0
lista = [ 'A','B','C','D']
for x in lista:
i+=1
if x == 'C':
break;
print(i)
But using index() of Wictor's response is simpler and more elegant.