How to list a column of float values from csv file without importing Python

Question

I had extracted some value from an excel file, like this:

with open("file.csv","r")  as file:

   data = file.readlines()[1:]

   for lines in data:

        lines = lines.split(",")

        A=float(lines[4])

From the above, i got a column of float when i type print(A), and there are a total of a thousand value (in a vertical column in the shell). If i want to have those values become a list, how should i do?

like turning:

0.0

0.0

0.0

into [0.0,0.0,0.0,...]

There is one restriction, not allowed to import any modules.

Answer 1

Using the default CSV module

Demo:

import csv
with open(filename, "r") as infile:
    reader = csv.reader(infile, delimiter=' ')
    OutputList = [map(float, list(i)) for i in zip(*reader)]

print(OutputList)

Output:

[[1.0, 2.0, 3.0, 4.0, 5.0], [0.0, 0.0, 0.0, 0.0, 0.0], [5.0, 4.0, 3.0, 2.0, 1.0]]

OR

You can make use of this too as given-below:

from itertools import izip_longest
import csv
with open(filename, "r") as infile:
    reader = csv.reader(infile, delimiter=' ')
    OutputList = [map(float, [j for j in list(i) if j is not None]) for i in izip_longest(*reader)]

print(OutputList)