Question

This is an exercise for a menu-driven program. Program should use shell functions. Write a program that displays the following menu:

Geometry Calculator

1. Calculate the area of a circle

2. Calculate the area of a rectangle

3. Calculate the area of a triangle

4. Quit

Enter your choice (1-4)

If the user enters 1, the program should ask for the radius of the circle and then display the area. Use the following formula to calculate the circle’s area: ? = ?? 2 where π=3.14159 and r is the radius of the circle.

If the user enters 2, the program should ask for the length and width of the rectangle and then display the rectangle’s area. Use the following formula to calculate the rectangle’s area: ???? = ?????ℎ ∗ ????ℎ

If the user enters 3, the program should ask for the length of the triangle’s base and its height, and then display its area. Use the following formula to calculate the area of the triangle: ???? = ???? ∗ ℎ???ℎ? ∗ .5

If user enters 4, the program should terminate

Answer 1

# Calculation of Area in Bash Shell
Area=0
count=0
while [ $count -eq 0 ]
do
echo "1. Calculate the area of circle"
echo "2. Calculate the area of rectangle"
echo "3. Calculate the area of triangle"
echo "4. Quit"
echo "Enter your choice (1-4)"
read choice

if [[ $choice -eq 1 ]]
then
        echo "Enter radius of circle "
        read radius
        Area= `expr 3.14 \* $radius \* $radius`
        echo "Area =  $Area" | bc`    
elif [[ $choice -eq 2 ]]
then
        echo "Enter length of a rectangle"
        read length
        echo "Enter width of a rectangle "
        read width
        Area = `expr $length \* $width`
        echo "Area = $Area" | bc`
elif [[ $choice -eq 3 ]]
then
        echo "Enter length of triangle base "
        read base
        echo "Enter length of triangle height "
        read height
        Area = ` expr $base \* $height \* 0.5`
        echo "Area =  $Area" 
else
        count=1
        exit
fi
echo "Do you continue (1 for y/ 0 for n)"
read ch
if [[ $ch -eq 1 ]]
then
        count=0
else
        exit
fi
done