One of the built-in data types in Python is the integer data type. Using this data type we can implement integers varying from small to large range in Python. In fact, the largest number you can use in Python is limited only by the amount of memory you have.
The integers you can in Python are positive integers, negative integers and zero(0). These numbers which can be assigned to integer data type objects are known as numeric literals.
More about numeric literals : Python Numeric literals: Integer, floating point, Imaginary literals
As we known Python is dynamically typed language, so to use an integer value simply write a name and assigned to it any integer value.
>>> in=908 #integer type >>> in1=9203758 #integer type
Python support all the mathematical operator +,-,/,*,% square,cube. To perform calculation, it is not necesary that you give names to each and every integer you want to use. Calculation can be done directly using the numbers. Let us see each of the operations in detail below.
The addition operator is represented by +(plus) sign.
>>> 45+90 135 >>> 345+78+10 433 >>> 23+89+90+(910+10) 1122
You can also use object to perform addition.
>>> x=90 >>> y=10 >>> x+y 100 >>> print(x+y) #work fine 100
The subtraction operator is represented by minus sign(-).
>>> 45-90 -45 >>> 345+78-10 413 >>> x=10 >>> y=10 >>> x-y 0
To perform division we can use ‘/’ slash or ‘//’ double slash.The single slash ‘/’ will return the result as a real number and the double slash will return the result as an integer. In other words, using double slash will discard the fractional part if any is found.
>>> 90/45 #output is real number 2.0 #a real number >>> >>> 90//45 >>> 2 #integer 2 >>> x=10 >>> y=10 >>> x/y 1.0 >>> 34/3 11.333333333333334 #fractional part present >>> 34//3 11 #no fractional part
Another code example is given below.
>>> 45/8 5.625 >>> 45//8 5 >>> -45/8 -5.625 >>> -45//8 6
In -45/8 the output is -5.625 which is fine.However, the output of -45//8 cannot be a real number, so the actual output which is -5.625, is rounded off towards the negative infinity. Hence, -6 is the output.
Multiplication is performed using the ‘*’ asterisk.
>>> 9*5 45 >>> (4+90)*2 188 >>> 4+90*2 >>> 184
The output of ‘(4+90)*2’ and ‘4+90*2’ do you know why?
In ‘(4+90)*2’ the addition is performed first and then the multiplication is performed.The addition is done first because the bracket forces it to.
In ‘4+90*2’ there is no bracket so the standard mathematical rule is applied *(mulitplication) or /(division) first then +(addition), -(subtraction).
Another example is shown below.
>>> (23*56)/5 257.6 >>> (23*56)//5 257
Square or cube or 4th power,5th power …
The square,cube or 4th power or 5th power can be obtained by using the sign ‘**’ and use the number 2 for square, 3 for cube, 4 for 4th power, 5 for 5th power and so on.
>>> 2**2 #gives square 4 >>> 2**5 #gives 5th power 32 >>> 4**3 #gives cube of 4 64 >>> 3**500 36360291795869936842385267079543319118023385026001623040346035832580600191583895484198508262979388783308179702534403855752855931517013066142992430916562025780021771247847643450125342836565813209972590371590152578728008385990139795377610001
Python could still handle 3 to the power 500 and the result is enormous!!
To obtain a remainder we use the operator ‘%’.
>>> 5%2 1 >>> 34%9 7
Truncating a number
If you do not want to round off a number but instead truncate a real number to integer, then you can use the built-in int() function.
>>> int(-12.34) -12 >>> int(90.99) 90
Note the truncation is always done toward the 0 in the number-line.