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COMPUTER SOFTWARE APPLICATION - CITS

Dictionary Items
Dictionary items are ordered, changeable, and do not allow duplicates.
Dictionary items are presented in key:value pairs, and can be referred to by using the key name.
Example

Print the “brand” value of the dictionary:
thisdict = {
“brand”: “Ford”,
“model”: “Mustang”,

“year”: 1964
}
print(thisdict[“brand”]
OUTPUT

Ford

Arrays

Note: This page shows you how to use LISTS as ARRAYS, however, to work with arrays in Python you will have
to import a library, like the NumPy library.

Arrays are used to store multiple values in one single variable:
Example
Create an array containing car names:
cars = [“Ford”, “Volvo”, “BMW”]

OUTPUT
[‘Ford’, ‘Volvo’, ‘BMW’]

What is an Array?
An array is a special variable, which can hold more than one value at a time.
If you have a list of items (a list of car names, for example), storing the cars in single variables could look like this:
car1 = “Ford”
car2 = “Volvo”
car3 = “BMW”
However, what if you want to loop through the cars and find a specific one? And what if you had not 3 cars, but
300?
The solution is an array!
An array can hold many values under a single name, and you can access the values by referring to an index
number.

Access the Elements of an Array
You refer to an array element by referring to the index number.

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CITS : IT&ITES - Computer Software Application - Lesson 120 - 137