Python3 Programming - Exercise 4 - Arithmetic Operators

Arithmetic Operators

Arithmetic operators are reserved symbols used for performing mathematical operations ( calculations).

Examples

operators	symbols	use	return type
Addition	+	1 + 3	int
Subtraction	-	3 - 1	int
Multiplication	*	3 * 2	int
Exponent	**	3 ** 2	int
Float division	/	3 / 2	float
Integer division	//	3 // 2	int
Modulo	%	3 % 2	int

Note

• If one of the operands is a float, then the resulting value is casted ( converted) into a float. Eg: 1.0 + 1 = 2.0 and 1 + 1 = 1 .
• // , returns the whole number part ( quotient) of the division. So, given: 22.0 // 3 = 7.0 and 22 // 3 = 7 .
• / , returns the quotient and the remainder as a float, together. Eg: 22 /3 = 7.333333333333333 and 0.25 / 0.5 = 0.5 .

Casting

Casting means, converting or changing from one type to another. To know the type of a value, use the type(obj) function. Eg: type(2) and type('2') will return <class 'int'> and <class 'str'> respectively. Meaning that 2 is an integer and '2' is a string.

Note

The values of x and y don't change after the casting, except that we do, y = float(y).

Practicals

write a program to evaluate and print the results of the following given that a = 2 and b = 5 :

1. • a _ (2 _ b) - 5
   • 2 * (b - a) + b
2. (-(a _ b) ** 2 - (4 _ a * b) ) / ((b // a) // 3 + (16 / a / b))
3. ((a ** 2) - (b ** 2)) // ((b - a) ** 2)
4. ((a + b) % 2) - ((b % a) + 1)

Summary

• +, -, *, **, /, //, % are reserved for mathematical operations.
• Rule of precedence is (), **, *, //, /, +, - .
• Use parentheses to change the precedence.