Re-arrange lists of lists in python-CodePudding

I need to turn this lists of lists into the following format. I accomplished this by creating a function and creating 4 additional lists to split the data into the required format. I was wondering if this could resolved in a simpler way.

The code I wrote is at the end.

Thanks.

values = 
[[100000.0, 36.0, 0.08, 20000.0],
 [200000.0, 12.0, 0.1, 0.0],
 [628400.0, 120.0, 0.12, 100000.0],
 [4637400.0, 240.0, 0.06, 0.0],
 [42900.0, 90.0, 0.07, 8900.0],
 [916000.0, 16.0, 0.13, 0.0],
 [45230.0, 48.0, 0.08, 4300.0],
 [991360.0, 99.0, 0.08, 0.0],
 [423000.0, 27.0, 0.09, 47200.0]]

This needs to be converted to column format as such:

[[100000.0,  200000.0,  628400.0,  4637400.0,  42900.0,  916000.0,  45230.0,  991360.0, 423000.0]
,[36.0, 12.0, 120.0, 240.0, 90.0, 16.0, 48.0, 99.0, 27.0]
,[0.08, 0.1, 0.12, 0.06, 0.07, 0.13, 0.08, 0.08, 0.09]
,[20000.0,  0.0,  100000.0,  0.0,  8900.0,  0.0,  4300.0,  0.0,  47200.0]]

def all_list(value):
    result = {}
    amount = []
    duration = []
    rate = []
    down_payment = []
    headers = parse_headers(file1[0])
    total = [amount, duration, rate, down_payment]
    for v in range(0,len(value)):
        amount.append(value[v][0])
        duration.append(value[v][1])
        rate.append(value[v][2])
        down_payment.append(value[v][3])
    for k,v in zip(total, headers):
        result[v] = k
    return result

CodePudding user response：

You are basically trying to transpose the 2-dimensional list. Here is an implementation to this.

def transpose(l1):
    l2 = []
    for i in range(len(l1[0])):
        row =[]
        for item in l1:
            row.append(item[i])
        l2.append(row)
    return l2

CodePudding user response：

Use zip with the * operator:

>>> values = [[100000.0, 36.0, 0.08, 20000.0],
...  [200000.0, 12.0, 0.1, 0.0],
...  [628400.0, 120.0, 0.12, 100000.0],
...  [4637400.0, 240.0, 0.06, 0.0],
...  [42900.0, 90.0, 0.07, 8900.0],
...  [916000.0, 16.0, 0.13, 0.0],
...  [45230.0, 48.0, 0.08, 4300.0],
...  [991360.0, 99.0, 0.08, 0.0],
...  [423000.0, 27.0, 0.09, 47200.0]]
>>> list(zip(*values))
[(100000.0, 200000.0, 628400.0, 4637400.0, 42900.0, 916000.0, 45230.0, 991360.0, 423000.0), (36.0, 12.0, 120.0, 240.0, 90.0, 16.0, 48.0, 99.0, 27.0), (0.08, 0.1, 0.12, 0.06, 0.07, 0.13, 0.08, 0.08, 0.09), (20000.0, 0.0, 100000.0, 0.0, 8900.0, 0.0, 4300.0, 0.0, 47200.0)]

CodePudding user response：

There is a more concise way of doing it using comprehensions:

amount = [item[0] for item in value]
duration = [item[1] for item in value]
rate = [item[2] for item in value]
down_payment = [item[3] for item in value]

CodePudding user response：

This is a matrix transpose. Numpy has this built in like this

import numpy as np
ans = np.transpose(values)