Getting the maximum values of every column and storing those value to an array in python without pan-CodePudding

I have a text file which looks like:

I want to have an array of length (number_of_columns - 1) which will store the maximum values of each column respectively except for the last column.

So my output array for this above example will look something like : 7 3 4 5

I don't want to use pandas here. I am unable to understand how to proceed.

CodePudding user response：

Use:

with open(datafile) as infile:
    # convert each line to an iterable of ints
    rows = (map(int, line.strip()) for line in infile)
    
    # find the maximum per col, exclude the last one
    *res, _ = (max(col) for col in zip(*rows))
    print(res)

Output

[7, 3, 4, 5]

As an alternative:

with open(datafile) as infile:
    # convert each line to an iterable of ints exclude the last one
    rows = (map(int, line.strip()[:-1]) for line in infile)

    # find the maximum per col,
    res = [max(col) for col in zip(*rows)]
    print(res)

CodePudding user response：

[max(lst) for lst in zip(*[map(int,line) for line in data.split() if line])][:-1]

CodePudding user response：

Read the file:

with open("filename") as f:
    text = f.read()

Collect the columns, and get the maximums:

from collections import defaultdict

cols = defaultdict(list)
for line in text.split("\n"):
    for i, char in enumerate(line):
        cols[i].append(char)
list(map(max, cols.values()))

>>> ['7', '3', '4', '5', '9']