Lab 3: Introduction to long, double, and Math.pow


Due Friday, September 8 at 11:59 PM

Goals for This Lab

By the time you have completed this work, you should be able to:

Provided files:

Step-by-Step Instructions

Step 1: Answer Questions Regarding Types

Download the lab3questions.txt file, and edit it with a text editor of your choice. Answer the questions in the file. Be sure to use the appropriate formatting. Save your work in your own local copy of lab3questions.txt. Be sure to preserve the filename and file type!

Step 2: Edit LongAreaCalculation.java

Download the LongAreaCalculation.java file, and open it in jGrasp (or a text editor of your choice). The program you write should behave exactly the same as AreaCalculation.java from last week. The only difference is that instead of using int variables to store the width, height, and area, you should use long variables. Similarly, you should use nextLong() as opposed to nextInt(). An example run of the program is shown below, with user input in bold:

Enter width: 2147483647
Enter height: 14
Area: 30064771058

For full credit, the output of your program must match EXACTLY to the output shown above. Note that if you use int variables instead, your calculations will be incorrect, resulting in a different area shown above. As a hint, you may want to simply copy your code from your AreaCalculation.java solution, and then modify it to use long variables and nextLong(). Your code will overall look somewhat similar to LongAddTwo.java

Step 3: Edit DegreeConversion.java

Download the DegreeConversion.java file, and open it in jGrasp (or a text editor of your choice). The program you need to write will take a temperature in Celsius and convert it to Fahrenheit. Notably, the temperature received can be a floating-point value, and the result will be a floating-point value, so you will need to use double variables and nextDouble().

You can convert a temperature in Celsius to a temperature in Fahrenheit using the following formula, where C represents the input temperature in Celsius, and F represents the output temperature in Fahrenheit:

F = C * 1.8 + 32

An example run of the program is shown below, with user input in bold:

Enter temperature in Celsius: 41.75
Fahrenheit: 107.15

For full credit, the output of your program must match EXACTLY to the output shown above. Note that if you use int variables instead, your calculations will be incorrect, resulting in a different Fahrenheit temperature shown above.

Step 4: Edit CompoundInterest.java

Download the CompoundInterest.java file, and open it in jGrasp (or a text editor of your choice). The program you need to write will compute compound interest including principal. In order to perform this computation, your program will need to gather the following inputs from the user in the following order:

  1. Principle (P, a long value)
  2. Annual interest rate (R, a double value)
  3. Number of times interest is compounded per year (N, an int value)
  4. Number of years invested (T, an int value)

With the above information, the compound interest can be computed using the following formula, where A represents the result (the compound interest including principle):

A = P * (1 + R / N)(N * T)

Note that the result (A) can be a floating-point value, so it should be represented as a double if it has its own variable. Exponentiation can be performed with Math.pow; for example, 54 can be written in Java like so:

Math.pow(5, 4)

An example of exponentiation in practice can be seen in Exponentiation.java.

An example run of the program you must write is shown below, with user input in bold:

Enter principle (long): 500
Enter annual interest rate (double): 0.053
Enter number of times interest is compounded per year (int): 12
Enter number of years invested (int): 8
Compound interest including principal: 763.3178417090967

For full credit, the output of your program must match EXACTLY to the output shown above. If you do not use the correct variable types, your calculation will likely be incorrect and lead to output which is different from what is shown above.

Step 5: Turn in Your Solution Using Canvas

Log into Canvas, and go to the COMP 110L class. Click “Assignments” on the left pane, then click “Lab 3”. From here, you can upload your answers and your code. Specifically, you must turn in the following three files:

In addition, if you collaborated with anyone else, be sure to download collaborators.txt and write the names of the people you collaborated with in the file, one per line. Please submit this file along with the other four files.

You can turn in the assignment multiple times, but only the last version you submitted will be graded.