In the last Python post, we have seen Default parameters. In this article, it will be dedicated to Multiple Parameters, Parameter types, and tuples as parameters. Here is a recap from the last article on Python
- Seven steps to compile Python 3.5.0 from source
- Getting started with Python and Anjuta
- Starting up with Python – Part 1 – Numbers and Maths, Variables
- Starting up with Python – Part 2 – Modules and Functions, Strings
- Starting up with Python – Part 3 – Sequences and List, Slicing and Editing
- Starting up with Python – Part 4 – More list functions and Slicing lists
- Starting up with Python – Part 5 – Methods
- Starting up with Python – Part 6 – Sort and Tuples, Strings and stuffs, methods and Dictionary
- Starting up with Python – Part 7 – If statement, Else and elif statements
- Starting up with Python – Part 8 – Nesting and Comparison operators
- Starting up with Python – Part 9 – And and Or operators
- Starting up with Python – Part 10 – While, For, Infinite and Break Loops
- Starting up with Python – Part 11 – Building functions and Default parameters
27. Multiple Parameters
Now, we will see how to put multiple parameters in functions. A simple example where we want to make a profile for manager’s name having different ages. In the example below, we have the asterisk in front of ages to be able to define as many age we want.
>> def profile(name, *ages): ... print name ... print ages ...
The first value will be treated as a name and everything else after it will be considered as ages. Now, we can call the profile function.
>> profile ('toto', 20,30,40) toto (20, 30, 40)
The parameter ‘toto’ is treated as a name and other as ages.
28. Parameter types
Now, will we see how to use parameters to convert it into a dictionary? Let’s create a function. Imagine we have a hackers group in Mauritius and we will need to categorized how many are there in the south, center, east, west and north. The idea is to use a double asterisk in from of Mauritius.
>> def hackers(**mauritius): ... print mauritius ...>> hackers(south=1,center=3,east=1,west=0,north=0) {'west': 0, 'east': 1, 'north': 0, 'center': 3, 'south': 1}
This is how we get a dictionary instead of a tuple. Let’s now combine both to use a dictionary inside a parameter.
> def hackers(country,nickname,*age,**projects): ... print country, nickname ... print age ... print projects ... >>> hackers('mauritius', 'TheTunnelix', 29,30, tarsnap=2, kernel=1) mauritius TheTunnelix (29, 30) {'kernel': 1, 'tarsnap': 2}
29.Tuples as Parameters
Now, we will gather information from a dictionary and tuples and use that information as parameters. Instead of creating dictionaries, we can use pre-existing ones as parameters. Let’s look at the code below
>> def country(a,b,c): ... return a+b+c
Consider, I already have a tuple as indicated below and we can place the tuple inside the parameter.
>> sum=(4,2,7) >>> country(*sum) 13
As you can see it output the sum of it. The first star in front sum means that I am working with a tuple and 2 stars means working with a dictionary. In the example below, it gives an example of using the 2 stars.
>> def test(**hello): ... print hello ... >>> hackers={'mauritius':5,'india':2,'usa':10} >>> test(**hackers) {'mauritius': 5, 'india': 2, 'usa': 10}
This is useful when gathering data from an outside source.
