Calculate Area Put in Table Lisp

What is area calculation?

The area of a shape is the amount of space it occupies in two-dimensional space. Common formulas include:

In Lisp, we can implement these formulas as functions to calculate and display area values.

Lisp implementation

Here's a Common Lisp implementation for calculating area and displaying results in a table:

(defun calculate-area (shape &key length width radius base height)
  "Calculate area based on shape type."
  (cond
    ((equal shape 'rectangle) (* length width))
    ((equal shape 'circle) (* pi (expt radius 2)))
    ((equal shape 'triangle) (/ (* base height) 2))
    (t (error "Unknown shape: ~a" shape))))

(defun display-results (results)
  "Display calculation results in a table format."
  (format t "~%+-----------------+-----------+~%")
  (format t "| Shape           | Area      |~%")
  (format t "+-----------------+-----------+~%")
  (loop for (shape area) in results do
    (format t "| ~16a | ~9,2f |~%" shape area))
  (format t "+-----------------+-----------+~%"))

(defparameter *pi* 3.141592653589793d0)

The code defines functions to calculate area for different shapes and display results in a formatted table. The *pi* constant is defined for circle calculations.

Displaying results in a table

The display-results function formats the output as a table with columns for shape and area. Here's how it works:

1. Prints a header row with column labels
2. Loops through the results list
3. Formats each row with proper alignment
4. Prints a footer row to complete the table

This creates a clean, readable output that's easy to understand at a glance.

Example calculation

Let's calculate areas for different shapes and display them in a table:

(let ((results (list
                              (cons 'rectangle (calculate-area 'rectangle :length 5 :width 3))
                              (cons 'circle (calculate-area 'circle :radius 4))
                              (cons 'triangle (calculate-area 'triangle :base 6 :height 4)))))
  (display-results results))

This code calculates areas for a rectangle (5×3), circle (radius 4), and triangle (6×4), then displays them in a table format.