int() - Python Tutorial

 

int() Python Built-in Function

int() is a built-in function that will convert a floating point number or string to an integer type. If a user or our program returns a string or a float we can use the int() function to convert the number to integer. The int() function rounds the float down to the floor check the examples below.

int() Built-in Function Example

#int() Examples

#int() example
>>> int(8.7)
8

#int() example
>>> int(9.876)
9

#int() example
>>> int(5.3)
5

#int() example
>>> int(6)
6

#int() example
>>> int("5677")
5677

#This does not work we can not convert a float string but check next example
>>> int("5.98")
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: '5.98'

#The fix to above example
>>> int(float("5.98"))
5

If you have any questions about int() built-in function leave a comment below.

 

int()

How to Convert Number Types in Python - Python Numbers - Python Tutorial

How To Convert Number Types in Python

In this Python tutorial, we are going to explore how to convert number types in Python. When coding sometimes we need in order to convert our current integer to a float or our current float to integer. We can also convert strings to either integers or floating point numbers.  Python has a built-in function that will give us the ability to do this.

Int() Built-in Function

The int() built-in function gives the ability to convert either a floating point number to an integer or convert a string to an integer. The int() function will always round down when converting floating point numbers. We also cannot convert floating point number strings to integers but we can do it we will look at that later in this tutorial. Let’s take a closer look at some int() examples.

#int() built-in function

#convert floats to integers
>>> int(4.5)
4
>>> int(1.45643)
1

#convert string integers to integers
>>> int("5")
5
>>> int("9")
9

Float() Built-in Function

The float() built-in function gives us the ability to convert integers to floating point numbers and convert strings to floating point numbers let’s take a closer look at this example.

#float() built-in function

#Convert integer to float
>>> float(6)
6.0

#convert integer to float
>>> float(-78)
-78.0

#convert integer in a string to a floating point number
>>> float("5")
5.0

#convert a floating point number string to a actual floating point number
>>> float("6.7")
6.7

Converting a String Floating Point Number To A Real Integer

#just using int will not work
>>> int("6.7")
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: '6.7'

#first convert to float then to integer
>>> int(float("6.7"))
6

Checking The Type Of An Object

We can also use the type() built-in function to check the type of an object.

#type()

>>> type(6)
<class 'int'>
>>> type(())
<class 'tuple'>
>>> type(7.6)
<class 'float'>
>>> type("")
<class 'str'>

Conclusion

 

In this Python tutorial, we took a look at How to Convert Number Types in Python. These built-in functions help us with our code so we do not have to build our own function to convert the number types. If you have any questions about this tutorial please leave a comment below.

How to Convert Number Types in Python - Python Numbers

Manually Adjust The Operator Precedence - Python Numbers - Python Tutorial

Manually Adjust The Operator Precedence

In the previous Python tutorial, we took a look at how Python evaluates equations using the operator precedence. In this Python tutorial, we are going to throw out all the information you learned in the previous tutorial and show you how you can control the operator precedence with parentheses in your equations.

Python will evaluate parentheses first then default to the operator precedence. This gives us the ability to adjust how Python will run an equation and gives us more control over our mathematical equations in our programs.

The Operator Precedence

A little review how the operator precedence is evaluated in Python.

1. **


2. *, /, %, //


3. +, -

In the default operator precedence exponent(**) will always run before any other operator.  Then multiplication(*), true division(/), modulo(%), and floor division(//) will run after the exponent(**).  Then finally addition(+) and subtraction(-) will run.

If an equation contains operators in the precedence like addition(+) and subtraction(-) then the equation will run left to right.

Manually Adjust The Operator Precedence

With Python we have the ability to manually adjust the operator precedence using parentheses which Python will run first then go to the default operator precedence after running the equation in the parentheses. This option gives us more control over our code and helps control flow of our math equations.

Manually Adjust The Operator Precedence Examples

#Manually Adjust The Operator Precedence Examples

#Default Operator Precedence Exponent first
>>> 2 ** 2 + 2
6

#Still runs exponent first
>>> 2 + 2 ** 2
6

#runs addition 
>>> (2 + 2) ** 2
16

#runs left to right
>>> 3 * 8 / 2
12.0

#runs division first
>>> 3 * (8 / 2)
12.0

#runs division first
>>> 6 * (7 / 4)
10.5

#test the equation
>>> 7/4
1.75

#test the equation
>>> 1.75 * 6
10.5

#Python runs multiplication first
>>> 6 + 5 - 3 + 4 * 10
48

#Python runs addition and subtraction first
>>> (6 + 5 - 3 +4) * 10
120

Conclusion 

In this tutorial, we learned how to Manually Adjust the Operator Precedence which gives us more control over our code and gives the flexibility to write quality programs. It is important to know that Python will default to its operator precedence after running the parentheses.

If you have any questions leave a comment below and we will do our best to help you out.

 

 

Manually Adjust The Operator Precedence - Python Numbers

round() is a build-in function in the Python Programming Language which gives us the ability to round a floating point number to the closest multiple of 10. It is important to understand that round() function takes a floating point number which has been convert from a fraction so sometimes the round() may return some numbers a different than you expect.

round() Syntax

round(floating point number, numbers after the decimal)

Round() only takes floating point numbers which is our first argument and the second argument is how many numbers positions do you want after the decimal point. If you do not provide a second argument python will return a integer type number as the default.

round() Examples

#round() Examples

#round() with no second argument
>>> round(1.7)
2

#round() with an second argument of 1
>>> round(1.76, 1)
1.8

#round() example with an second argument of 4
>>> round(1.56787, 4)
1.5679

Weird Round() Returns

round(0.5) – returns 0 but we would expect this to return 1

round(2.675, 2) - returns 2.67 but in reality it should be 2.68.  Python returns 2.67 because this number is convert to a fraction and then converted back from a fraction and the conversion is not exact the actual return for 2.67 is 2.67499999999999982236431605997495353221893310546875

round()

deallocation - Python Tutorial

Deallocation is the process Python uses to remove reserved memory. This process is done by Python’s memory management process.

deallocation

allocation - Python Tutorial

Allocation is how Python distributes space for memory in Python programs.  Allocation is part of the Python memory management process.

allocation

Operator Precedence in Python - Python Numbers - Python Tutorial

Operator Precedence in Python

In this Python tutorial, we are going to look at operator precedence in Python. We will be focusing on the operators we have already learned like **, *, /, //, %, + and -. It is important to understand what operator will run first.

Operator Precedence

The list below will show which operator has more precedence over the operators.  So the first operator in the list will run before the second operator below.

1. ** – Exponent


2. *, /, %, // – Multiplication, true division, modulo, floor division.  In this case if these operators where in the same equation then the equation would run left to right.


3. +, – Addition and Subtraction are the last operators to run.

Operator Precedence Examples

Let’s look at some examples and figure out which operator will run in the equation. The order in which the operators run could have some serious effects on your results.

Exponent and Multiplication

Exponent will always run before the multiplication equation. Take a look at the example.

#Exponent and Multiplication

#Exponent Runs First

>>> 2 ** 2 * 2
8

#If multiplication ran first this answer would be 16
>>> 2 * 2 ** 2
8

Exponent and Division

Exponent will always run before a division equation. Take a look at this example.

#Exponent and Division

#exponent runs first
>>> 4 / 2 ** 6
0.0625

#2 ** 6 is 64
>>> 4 / 64
0.0625

Multiplication and Division

In this scenario Python will run the equation from left to right since multiplication and division have the precedence. Take a look at the example below.

#Multiplication and Division

#In this case division is ran first then multiplied by 3
>>> 5 / 4 * 3
3.75

#In this case 3 is multiplied by 4 then divided by 5
>>> 3 * 4 / 5
2.4

Multiplication and Addition

Multiplication will run before an addition equation since multiplication has more precedence over addition. Here is an example.

#Multiplication and Addition

>>> 2 + 4 * 4
18

Addition and Subtraction

In this scenario the equation will run left to right since addition and subtraction are on the same level.

#Addition and Subtraction

>>> 2 + 3 - 5 + 8 - 4 + 2 - 9
-3

Conclusion

In this Python tutorial, we took a look at Operator Precedence in Python it is important to remember which operator will run first because you can end up with different values if you are not paying attention when setting up your equations. In the next Python tutorial, we will look at a way to manually change the order.

Operator Precedence in Python - Python Numbers