Python - Dictionary

Introduction

Python dictionary data structure is like a map in another language like java or associative array in php. It's use a name value pairs.

How To

You use bracket for declaring and defining it. Here's a code.

Program Code

data = {"name":"lady gaga", "city":"new york", "age":24}
print data

Output

{"name":"lady gaga", "city":"new york", "age":24}

Accessing And Modifying Element

For accessing a value, you use its name. For example, you want to access name value, so you use its name key.

Program Code

data = {"name":"lady gaga", "city":"new york", "age":24}
print "Name: ", data["name"]
print "City: ", data["city"]
print "Age: ", data["age"]

Output

Name: lady gaga
City: new york
Age: 24

You can also change the value of a map. If you want to change, use the key. Here, for example, we want to change the name to be "jenifer lopez"

Program Code

data = {"name":"lady gaga", "city":"new york", "age":24}
data["name"] = "jenifer lopez"
print data

Output

{"city":"new york", "name":"jenifer lopez", "age":24}

Iterating Elements

Here's a code that just iterate for the keys

Program Code

data = {"name":"lady gaga", "city":"new york", "age":24} for item in data:     print item

Output

city
age
name

May you ask, why just the keys? I don't know how to answer the reason, but it's not so bad bacause we just can get the keys - we can get the values by the keys.

Program Code

data = {"name":"lady gaga", "city":"new york", "age":24}
for key in data:
    print data[key]

Output

new york
lady gaga
24

Python - Dictionary