How to turn a list containing strings into a list containing integers (Python)

Question

I am optimizing PyRay ( https://github.com/oscr/PyRay ) to be a usable Python ray-casting engine, and I am working on a feature that takes a text file and turns it into a list (PyRay uses as a map). But when I use the file as a list, it turns the contents into strings, therefore not usable by PyRay. So my question is: How do I convert a list of strings into integers? Here is my code so far. (I commented the actual code so I can test this)

print("What map file to open?")
mapopen = input(">")

mapload = open(mapopen, "r")
worldMap = [line.split(',') for line in mapload.readlines()]
print(worldMap)

The map file:

1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,
1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,
2,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
1,0,2,0,0,3,0,0,0,0,0,0,0,2,3,2,3,0,0,2,
2,0,3,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
1,0,0,0,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,2,
2,3,1,0,0,2,0,0,0,2,3,2,0,0,0,0,0,0,0,1,
1,0,0,0,0,0,0,0,0,1,0,1,0,0,1,2,0,0,0,2,
2,0,0,0,0,0,0,0,0,2,0,2,0,0,2,1,0,0,0,1,
1,0,0,0,0,0,0,0,0,1,3,1,0,0,0,0,0,0,0,2,
2,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
1,0,2,0,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,2,
2,0,3,0,0,2,0,0,0,0,0,0,0,2,3,2,1,2,0,1,
1,0,0,0,0,3,0,0,0,0,0,0,0,1,0,0,2,0,0,2,
2,3,1,0,0,2,0,0,2,1,3,2,0,2,0,0,3,0,3,1,
1,0,0,0,0,0,0,0,0,3,0,0,0,1,0,0,2,0,0,2,
2,0,0,0,0,0,0,0,0,2,0,0,0,2,3,0,1,2,0,1,
1,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,3,0,2,
2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,3,0,0,0,1,
2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,

Please help me, I have been searching all about and I can't find anything.

Answer 1

try this: Did you want a list of lists? or just one big list?

with open(filename, "r") as txtr:
    data = txtr.read()
data = txtr.split("/n")  # split into list of strings
data = [ list(map(int, x.split(","))) for x in data]

fourth line splits string into list by removing comma, then appliea int() on each element then turns it into a list. It does this for every element in data. I hope it helps.

Here is for just one large list.

with open(filename, "r") as txtr:
    data = txtr.readlines()  # remove empty lines in your file!
data = ",".join(data)  # turns it into a large string
data = data.split(",")  # now you have a list of strings
data = list(map(int, data))  # applies int() to each element in data.

Answer 2

Look into the map built-in function in python.

L=['1', '2', '3']
map = map(int, L)
for el in map:
    print(el)

>>> 1
... 2
... 3

Answer 3

As per you question, please find below a way you can change list of strings to list of integers (or integers if you use list index to get the integer value). Hope this helps.

myStrList = ["1","2","\n","3"]

global myNewIntList 

myNewIntList = []

for x in myStrList:
    if(x != "\n"):
        y = int(x)
        myNewIntList.append(y)


print(myNewIntList)