I am a python newbie. I saw a code which had * inside a print function // print(*a) // in which 'a' was a list. I know * is multiplication operator in python, but don't know what's it in a list
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Does this answer your question? [What does \*\* (double star/asterisk) and \* (star/asterisk) do for parameters?](https://stackoverflow.com/questions/36901/what-does-double-star-asterisk-and-star-asterisk-do-for-parameters) – Eric Jin May 25 '20 at 18:21
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It'd print all items without the need of looping over the list. The * operator used here unpacks all items from the list.
a = [1,2,3]
print(a)
# [1,2,3]
print(*a)
# 1 2 3
print(*a,sep=",")
# 1,2,3
Lubdhak
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(If you don't know about the variable number of argument methods, leave this topic and learn this after that)
Unpacking elements in list
Consider new_list = [1, 2, 3]. Now assume you have a function called addNum(*arguments) that expects 'n' number of arguments at different instances.
case 1: Consider calling our function with one parameter in the list. How will you call it? Will you do it by addNum(new_list[0])?
Cool! No problem.
case 2: Now consider calling our function with two parameters in the list. How will you call it? Will you do it by addNum(new_list[0], new_list[1])?
Seems tricky!!
Case 3: Now consider calling our function with all three parameters in the list. Will you call it by addNum(new_list[0], new_list[1], new_list[2])? Instead what if you can split the values like this with an operator?
Yes! addNum(new_list[0], new_list[1], new_list[2]) <=> addNum(*new_list)
Similarly, addNum(new_list[0], new_list[1]) <=> addNum(*new_list[:2])
Also, addNum(new_list[0]) <=> addNum(*new_list[:1])
By using this operator, you could achieve this!!
Maria Irudaya Regilan J
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Thank you for such a detailed explanation about the Variable number of argument methods. – AJAY P May 27 '20 at 18:08