Print List of Lists in Separate Lines

Print list of lists in separate lines

Iterate through every sub-list in your original list and unpack it in the print call with *:

a = [[1, 3, 4], [2, 5, 7]]
for s in a:
    print(*s)

The separation is by default set to ' ' so there's no need to explicitly provide it. This prints:

1 3 4
2 5 7

In your approach you were iterating for every element in every sub-list and printing that individually. By using print(*s) you unpack the list inside the print call, this essentially translates to:

print(1, 3, 4)  # for s = [1, 3, 4]
print(2, 5, 7)  # for s = [2, 5, 7]

How to print a list of lists in different lines?

To answer your question, we must inspect the unpacking operator (*) and how it works with print.

Recall that the unpacking operator takes a single iterable and turns it into multiple elements which are passed in series to a function.

Then, we know that print takes multiple arguments in the form of args, using a separator to separate them, if necessary. With this in mind, we can see that the four ways to print a b c are equivalent:

print('a', 'b', 'c')
print(*['a', 'b', 'c'])
print(sep.join(['a', 'b', 'c']))
print('a' + sep + 'b' + sep + 'c')

...where sep is, by default, (a single space).

Now, we note that m is a nested list. Therefore, by doing print(*m), what you are doing is effectively print(m[0], m[1]...m[-1]), where m[0], m[1]...m-1 are individually lists.

By referring to our analysis of print above, we can see that that is the same as print(m[0] + ' ' + m[1] + ' ' + ... + ' ' + m[-1]).

Clearly, there are no newlines in that, but there should be newlines where there are now spaces.

To get what we want, which is a newline after each element, therefore, we can just do print(*m, sep='\n').

How can I format a list to print each element on a separate line in python?

You can just use a simple loop: -

>>> mylist = ['10', '12', '14']
>>> for elem in mylist:
        print elem 

10
12
14

Print a nested list line by line - Python

Use a simple for loop and " ".join() mapping each int in the nested list to a str with map().

Example:

>>> ys = [[1, 2, 3], [4, 5, 6], [7, 8, 9, 10]]
>>> for xs in ys:
...     print(" ".join(map(str, xs)))
... 
1 2 3
4 5 6
7 8 9 10

The difference here is that we can support arbitrary lengths of inner lists.

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The reason your example did not work as expected is because your inner loop is iterating over each element of the sub-list;

for r in A:  # r = [1, 2, 3]
    for t in r:  # t = 1 (on first iteration)
        print(t,)
    print

And print() by default prints new-line characters at the end unless you use: print(end="") I believe if you were using Python 2.x print t, would work. For example:

>>> ys = [[1, 2, 3], [4, 5, 6], [7, 8, 9, 10]]
>>> for xs in ys:
...     for x in xs:
...             print x,
...     print
... 
1 2 3
4 5 6
7 8 9 10

But print(x,) would not work as you intended it; Python 2.x or 3.x

how can I split a list and print it in separate lines?

If you want to output the list new-line separated you can use #join and use the newline-character (\n) as separator for your list entries.

For example:

bot.send_message(chat_id = update.message.chat_id , text = "\n".join(list))

which will output:

username1
username2
username3

If you explicitly want the [ & ] outputed as well, you can use format to add them:

text = "[\n{}\n]".format("\n".join(list))
bot.send_message(chat_id = update.message.chat_id , text = text)

How to split a list of lists dynamically with next line separator

You can join the elements per row using ', ' as separator, then join the rows with a newline and print:

list_of_lists = [['England', '90.0%'], ['Scotland', '10.0%']]

print('\n'.join(map(', '.join, list_of_lists)))

output:

England, 90.0%
Scotland, 10.0%

Python - Output Elements in Two Lists on Separate Lines

Given:

>>> li1=['Chapter One Test', 'Chapter Two Test', 'Chapter Three Test']
>>> li2=['84%', '75%', '90%']

You can zip the two lists together:

>>> print('\n'.join(['{}\t{}'.format(*t) for t in zip(li1,li2)]))
Chapter One Test    84%
Chapter Two Test    75%
Chapter Three Test  90%

If you want to make a table, you might make the field widths fixed rather than \t separated:

>>> print('\n'.join(['{:22s}{:3s}'.format(*t) for t in zip(li1,li2)]))
Chapter One Test      84%
Chapter Two Test      75%
Chapter Three Test    90%

Read more about format mini-language to find out more about those options.

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