Question

Is the division statement in the following code an example of integer division or floating-point division? What valuc will be stored in portlon? double portion: portan \(=70 / 3\)

Short answer

Answer: The given code performs integer division, and the value stored in the variable 'portion' is 23.0.

Step-by-step solution

Identify the type of division

In this step, check if the division operation is an integer division or floating-point division. Since both the numerator (70) and the denominator (3) are integers, the division is an integer division.

Perform the division

Perform the integer division: 70 / 3 = 23 (remainder 1). The result is an integer.

Convert the result to a floating-point number

As the result of the division is going to be stored in a variable of type 'double', which can store floating-point numbers, the integer result must be converted to a floating-point number. The integer result 23 can be represented as the floating-point number 23.0.

Store the result in the variable 'portion'

Now that we have the floating-point representation of the result, we can store it in the variable 'portion': portion = 23.0. In conclusion, the division statement in the given code is an example of integer division. The value 23.0 will be stored in the variable 'portion'.

Key concepts

Integer Division

Integer division occurs when both operands in a division operation are integers. In Java Programming, this means that the division does not calculate the decimal part of the quotient. Instead, it provides the greatest integer less than or equal to the actual decimal result.
This process essentially calculates the whole number portion of the division result only, without considering the remainder. For example, in the case of dividing 70 by 3, since both are integers, the result would be 23 with a remainder of 1.
It's crucial for students to remember that integer division may lead to a loss of precision, especially when expecting a fractional result.

Floating-point Division

Floating-point division differs from integer division in that it can handle numbers with fractional parts. This type of division takes place when either or both of the operands are floating-point numbers in Java, such as float or double.
The result of a floating-point division retains the full quotient, including the decimal part, which offers precision and makes it ideal for scientific calculations or scenarios where accuracy is crucial.

• In Java, if an operation involves a floating-point type, the result will naturally be a floating-point number.
• To perform floating-point division explicitly, ensure at least one operand is a decimal, such as writing 70.0 / 3 or casting one of the operands.

If the division in our example was written as 70.0 / 3 instead, it would perform a floating-point division and yield 23.3333 as a result.

Type Conversion

Type conversion, or casting, is a means of converting a variable from one data type to another in Java. This is especially relevant when dealing with the result of a division that needs to be stored in a variable of a different type.
For integer division results needing to be stored in a double variable, Java automatically performs widening conversion. This converts an integer to a double, ensuring no data is lost since double has a larger capacity and can store decimals.

• Explicit casting is needed when narrowing conversion is required, such as converting a double to an int, where precision is lost.
• Implicit casting happens automatically in Java when types are compatible and no loss of information occurs.

Understanding how Java handles these conversions helps prevent errors and ensures that storage into variables occurs correctly.

Variables

In Java, variables are storage locations with names and types assigned to hold data. Understanding how to declare and use them is foundational. A variable's type determines what kind of data it can store, such as integers, doubles, characters, etc.
For example, in the statement `double portion`, 'portion' is a variable that is meant to store a floating-point number.

• Java requires variables to be declared with a specific type before use, ensuring that it holds the correct form of data.
• Variable initialization assigns a value to this storage location; without it, the variable may have an undefined state.

In our exercise, 'portion' is of type double, making it suitable to store a value like 23.0, which results from converting the integer division result into a float.