Python Numbers, Type Conversion, and Mathematics: In this article, you’ll find out about the various numbers used in Python, how to convert from one data type to the other, and the mathematical operations supported in Python.
Number Data Type in Python
Python supports integers, floating-point numbers, and complex numbers. They are characterized as int, float, and complex classes in Python.
Integers and floating points are separated by the nearness or nonappearance of a decimal point. For example, 5 is a whole number though 5.0 is a gliding point number.
Complex numbers are written in the structure, x + yj, where x is the real part, and y is the imaginary part.
We can use the type() function to know which class a variable or a worth has a place with and isinstance() function to check in the event that it has a place with a specific class.
Let’s look at an example:
a = 5 print(type(a)) print(type(5.0)) c = 5 + 3j print(c + 3) print(isinstance(c, complex))
When we run the above program, we get the following output:
<class 'int'> <class 'float'> (8+3j) True
While integers can be of any length, a drifting point number is precise just up to 15 decimal places (the sixteenth spot is incorrect).
The numbers we manage each day are of the decimal (base 10) number framework. In any case, software engineers (by and large inserted developers) need to work with paired (base 2), hexadecimal (base 16), and octal (base 8) number systems.
In Python, we can represent these numbers by appropriately placing a prefix before that number. The accompanying table lists these prefixes.
|Binary||‘0b’ or ‘0B’|
|Octal||‘0o’ or ‘0O’|
|Hexadecimal||‘0x’ or ‘0X’|
Here are some examples
# Output: 107 print(0b1101011) # Output: 253 (251 + 2) print(0xFB + 0b10) # Output: 13 print(0o15)
When you run the program, the output will be:
107 253 13
We can convert one type of number into another. This is also known as coercion.
Operations like addition, subtraction coerce integer to float implicitly (automatically), if one of the operands is float.
>>> 1 + 2.0 3.0
We can see above that 1 (integer) is coerced into 1.0 (float) for addition and a result is also a floating-point number.
We can also use built-in functions like
complex()to convert between types explicitly. These functions can even convert from strings.
>>> int(2.3) 2 >>> int(-2.8) -2 >>> float(5) 5.0 >>> complex('3+5j') (3+5j)
When converting from float to integer, the number gets truncated (decimal parts are removed).
Python built-in class float performs some calculations that might amaze us. We all know that the sum of 1.1 and 2.2 is 3.3, but Python seems to disagree.
>>> (1.1 + 2.2) == 3.3 False
What is going on?
It turns out that floating-point numbers are implemented in computer hardware as binary fractions as the computer only understands binary (0 and 1). Due to this reason, most of the decimal fractions we know, cannot be accurately stored in our computer.
Let’s take an example. We cannot represent the fraction 1/3 as a decimal number. This will give 0.33333333… which is infinitely long, and we can only approximate it.
It turns out that, the decimal portion 0.1 will bring about an endlessly long parallel part of 0.000110011001100110011… what’s more, our computer just stores a limited number of it.
This will just approximate 0.1 however never be equivalent. Thus, it is the confinement of our computer hardware and not an error in Python.
>>> 1.1 + 2.2 3.3000000000000003
To overcome this issue, we can use the decimal module that accompanies Python. While gliding point numbers have accuracy up to 15 decimal places, the decimal module has client settable precision.
Let’s see the difference:
import decimal print(0.1) print(decimal.Decimal(0.1))
This module is used when we want to carry out decimal calculations as we learned in school.
It also preserves significance. We know 25.50 kg is more accurate than 25.5 kg as it has two significant decimal places compared to one.
from decimal import Decimal as D print(D('1.1') + D('2.2')) print(D('1.2') * D('2.50'))
Notice the trailing zeroes in the above example.
We might ask, why not implement
Decimal every time, instead of float? The main reason is efficiency. Floating point operations are carried out must faster than
When to use Decimal instead of float?
We generally use Decimal in the following cases.
when we are making financial applications that need careful decimal representation.
when we want to control the degree of exactness required.
when we want to execute the notion of significant decimal spots.
Python provides operations involving fractional numbers through its fractions module.
A fraction has a numerator and a denominator, the two of which are whole numbers. This module has support for discerning number-arithmetic.
We can make Fraction questions in different ways. Let’s have a look at them.
import fractions print(fractions.Fraction(1.5)) print(fractions.Fraction(5)) print(fractions.Fraction(1,3))
3/2 5 1/3
float, we might get some unusual results. This is due to the imperfect binary floating point number representation as discussed in the previous section.
Fraction allows us to instantiate with string as well. This is the preferred option when using decimal numbers.
import fractions # As float # Output: 2476979795053773/2251799813685248 print(fractions.Fraction(1.1)) # As string # Output: 11/10 print(fractions.Fraction('1.1'))
This data type supports all basic operations. Here are a few examples.
from fractions import Fraction as F print(F(1, 3) + F(1, 3)) print(1 / F(5, 6)) print(F(-3, 10) > 0) print(F(-3, 10) < 0)
2/3 6/5 False True
Python offers modules like math and random to carry out different mathematics like trigonometry, logarithms, probability, and statistics, etc.
import math print(math.pi) print(math.cos(math.pi)) print(math.exp(10)) print(math.log10(1000)) print(math.sinh(1)) print(math.factorial(6))
3.141592653589793 -1.0 22026.465794806718 3.0 1.1752011936438014 720
import random print(random.randrange(10, 20)) x = ['a', 'b', 'c', 'd', 'e'] # Get random choice print(random.choice(x)) # Shuffle x random.shuffle(x) # Print the shuffled x print(x) # Print random element print(random.random())
When we run the above program we get the output as follows. (Values may be different due to the random behavior)
18 e ['c', 'e', 'd', 'b', 'a'] 0.5682821194654443
Please feel free to give your comment if you face any difficulty here.
For More Latest Articles Click on Below Link.