如何使用现有的 arrays 创建新阵列？

Question

If I have some arrays:

a1,
a2,
a3,
a4

How can I use them to build a new array like this:

result = [
    [[28604,77,17096869,'Australia',2015],[31163,77.4,27662440,'Australia',1990]],
    [[44056,81.8,23968973,'Canada',1990],[43294,81.7,35939927,'Canada',2015]]
];

If I print the 0th row of result, it will output [[28604,77,17096869,'Australia',2015],[31163,77.4,27662440,'Australia',1990]] as an array.

print(result[0])
output:  [[28604,77,17096869,'Australia',2015],[31163,77.4,27662440,'Australia',1990]]

Answer 1

Here you go, creating a list of list which every list contains two lists.

a1 = [28604,77,17096869,'Australia',2015]
a2 = [31163,77.4,27662440,'Australia',1990]
a3 = [44056,81.8,23968973,'Canada',1990]
a4 = [43294,81.7,35939927,'Canada',2015]

result = [
    [a1, a2],
    [a3, a4]
]
print(result[0])

Answer 2

The question isn't clear on how exactly you are trying to do that. In the simplest way, You can directly put them into results while initializing the list. You can do it like -

a1=[28604,77,17096869,'Australia',2015]
a2=[31163,77.4,27662440,'Australia',1990]
a3=[44056,81.8,23968973,'Canada',1990]
a4=[43294,81.7,35939927,'Canada',2015]

result=[[a1,a2],[a3,a4]]
print(result)
print(result[0])

OUTPUT:

[[[28604, 77, 17096869, 'Australia', 2015], [31163, 77.4, 27662440, 'Australia', 1990]], [[44056, 81.8, 23968973, 'Canada', 1990], [43294, 81.7, 35939927, 'Canada', 2015]]]
[[28604, 77, 17096869, 'Australia', 2015], [31163, 77.4, 27662440, 'Australia', 1990]]

Answer 3

The desired behaviour of your question is a little unclear, but I am sure you can achieve what you're trying to do using either

new_array.append(a1)

or

new_array += a1