Convert element of list to integer(Two dimentional array)

Convert element of list to integer(Two dimentional array) - Printable Version

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Convert element of list to integer(Two dimentional array) - zorro_phu - Jun-11-2018

I'm trying to learn arrays(with numpy) in python3 but i am not able to figure out how do i convert the elements of list to integer(in my case i have two dimentional array). I've tried two solutions that i found(its mentioned in the code) but it gives me error. Can someone help me? Thank you.
My main objective is to get inputs and store them like a matrix(for example like 3x3) so that later i can take any elements of the list and perform any operation on them.
[inline]

from numpy import array

r,c=input("Number of row and cloumn:").split('x')
r=int(r)
c=int(c)
m=[]

for i in range(r):
    row_col=input("Row values:").split()
    m.append(row_col)
    
m=list(map(int,m)) #not working
# m=[int(i) for i in m] not working

m=array(m)
print(m)
print(m[0:1,0:1])

[/inline]

Output:
TypeError: int() argument must be a string, a bytes-like object or a number, not 'list'

If i dont use the conversion( m=list(map(int,m)) ) then i get

Output:Number or row and cloumn:3x3
Row values:1 2 3
Row values:4 5 6
Row values:7 8 9
[['1' '2' '3']
 ['4' '5' '6']
 ['7' '8' '9']]
[['1']]

My expected output

Output:Row values:1 2 3
Row values:4 5 6
Row values:7 8 9
[[1, 2, 3]
 [4, 5, 6]
 [7, 8, 9]]
[[1]]

RE: Convert element of list to integer(Two dimentional array) - killerrex - Jun-11-2018

You need to transform each row first to integer, either when you read the values:

for i in range(r):
    row = input("Row values:")
    m.append([int(s) for s in row.split()])

Or later:

m = [[int(s) for s in row] for row in m]

Remember that numpy only transforms a matrix given as a list of lists to a 2D array if all the lists have the same number of elements, so you might want to use the c value that you are not using to guarantee that the user inputs the right number of elements (or to add 0 or truncate as needed)

RE: Convert element of list to integer(Two dimentional array) - Larz60+ - Jun-11-2018

Or you could use the following which will allow mixed numbers and strings:

>>> mylist = ['1', '4', '6', '8', 'hello', '7']
>>> newlist = [int(item) if item.isdigit() else item for item in mylist]
>>> newlist
[1, 4, 6, 8, 'hello', 7]
>>>

RE: Convert element of list to integer(Two dimentional array) - zorro_phu - Jun-12-2018

Thanks a lot. I'll try all the solutions.