Python programmers often have problem with their script. Their script cannot run well, often because of the incorrect data type. Some of the different data types can not work in one operation and python give error result.
In this article, we will show 5 data type in python. Python has five standard Data Types.
The Python data types are: numbers, strings, list, tuple, and dictionary.
- Numbers
- Integer
- Float Point Number
- Complex Number
- Strings
- List
- Tuple
- Dictionary
This is something that every programmer need to know. It help us to prevent error and make dream program into reality.
After reading this article, you can prevent error that stop program. You can also imagine more about what program can do. There
First, let’s talk about numbers
Numbers
“The most used number data type is integer and floating. But that is not the only number data type in python. Python has another number data type. There is complex, decimals and fractions.
Integer
Integer is the whole number without fractional number. It includes positive, negative and zero number. But it does not include 1.5, because that is a fractional number. 50% is not an integer because it is a fractional number. Example of integer is -60, 31, 0, 50 38. and so on.
If we assign integer number to a variable, python automatically defines its number and variable as an integer.
In Python programming language, declaration data as number is simple. Write a variable and assign a number without punctuation.
This is an example. Var1 = 23. This is make var1 as number integer data type. Yo can check the type of variable by writing “type(var)” in python.
>>> var = 34
>>> type(var)
<type 'int'>
Float Point Number
Float point number is fractional number or decimal number. The fractional part or decimal part of a non‐negative real number is the excess beyond that number’s integer part. For example 0.1, 5.1.
In python, to define that some variable as float type, we just assign float point number to a variable. For example, we have variable C and data float point, 1.3.
>>> c= 1.3 # dot in this number is sign of decimal number after dot.
>>> type(c)
<type 'float'>
It is possible in python to make mathematic operatation between float and integer. For example
>>> c= 1.3
>>> type(c)
<type 'float'>
>>> d = 29
>>> type(d)
<type 'int'>
>>> w = c+d
>>> w
30.3
>>> type(w)
<type 'float'>
Python support operand type(s) for float and integer.
Complex Number
Complex number is a combination of real number and imaginative number. The syntax of complex number is , + j. We has to add “j” to imaginary part. Example
>>> 3+6j
(3+6j)"
Strings
strings are sequences of alphabet, text, or number data. It is character data. Number as character data different than gives integer. If we assign number as character data, we can not make mathematic operation correctly.
To make python understand, that some data is strings is by add quote or double quote befor and after data. The data is include
This is example number as character data.
>>> x = '9' #
>>> type(x)
<type 'str'>
>>> x *5
'99999'
The example show that ‘9’ * 5 (‘9’ multiply 5) is not 45, but ‘99999’. Because, the ‘9’ is not integer, but string.
If the between string and integer is allowed, python cannot do the addition for them. It is example. Python give error message.
>>> x = '8'
>>> x*4
'8888'
>>> x +5
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: cannot concatenate 'str' and 'int' objects
>>>
List
A variable can have more than one data or lists. Python have 3 distinct lists. There are: list, tuple, and dictionary. In this section we talk about list.
List is a collection of values. It is series of values. Data type of values can be number or strings. List variables are declared by using brackets “[” and “]” following the variable name. See distinct of {}, (), and [] carefully.
Tuple is also collection of values. Unique feature of list compare to tuple is mutable. We change the member of list easily.
your_list = [2,3,4,5,6]
my_list = ["we', "are", "champion"]
empty_list = []
Python give index of every member of list. The index is start with 0. There are 0,1,2,3 and so on. So we can also retrieve the list by its index number. For example.
>>> ere = ["yes", 90, "wow"]
>>> ere[0]
'yes'
>>> ere[2]
'wow'
List can be member of another list.
>>> ere = ["yes", 90, "wow"]
>>> newlist = [ere, [3,5,"5"]]
>>> newlist
[['yes', 90, 'wow'], [3, 5, '5']]
>>>
We can retrieve list in the list by two bracket square.
>>> newlist
[['yes', 90, 'wow'], [3, 5, '5']]
>>> newlist[0][1]
90
>>>
Tuple
Tuple is also collection of value. Different than list data type, tuple data type immutable. We can not change its member easily.
It is simple to create a tuple. We can type colletion of value within parenthesis ().
>>> mytuple=(1,2,"three")
>>> type(mytuple)
<type 'tuple'>
>>>
Dictionary
Dictionary is also a collection of value. But different than list and tuple, dictionary, the values of dictionary are pair of key and value. Imagine about an english german dictionary. The list have pair of english word and its meaning in germany language.
eng2g = {"one": "eins", "two": "zwei", "three": "drei"}
To declare a variable as dictionary is simple. If list have bracket square [], tuple have parenthesis (), dictionary have {}. The pair of value have :
>>> gg ={}
>>> type(gg)
<type 'dict'>
>>>
