Python: Compute the area of the polygon

Python Basic - 1: Exercise-59 with Solution

A convex polygon is a simple polygon in which no line segment between two points on the boundary ever goes outside the polygon. Equivalently, it is a simple polygon whose interior is a convex set. In a convex polygon, all interior angles are less than or equal to 180 degrees, while in a strictly convex polygon all interior angles are strictly less than 180 degrees.

Write a Python program that compute the area of the polygon . The vertices have the names vertex 1, vertex 2, vertex 3, ... vertex n according to the order of edge connections.

Input:
Input number of sides: 5
Side: 1
Input the Coordinate:
Input Coordinate x: 1
Input Coordinate y: 0
Side: 2
Input the Coordinate:
Input Coordinate x: 0
Input Coordinate y: 0
Side: 3
Input the Coordinate:
Input Coordinate x: 1
Input Coordinate y: 1
Side: 4
Input the Coordinate:
Input Coordinate x: 2
Input Coordinate y: 0
Side: 5
Input the Coordinate:
Input Coordinate x: -1
Input Coordinate y: 1
Area of the Polygon: 0.5

Pictorial Presentation:

Sample Solution:

Python Code:

def poly_area(c):
  add = []
  for i in range(0, (len(c) - 2), 2):
    add.append(c[i] * c[i + 3] - c[i + 1] * c[i + 2])
    add.append(c[len(c) - 2] * c[1] - c[len(c) - 1] * c[0])
    return abs(sum(add) / 2)
no_sides = int(input('Input number of sides: '))
cord_data = []
for z in range(no_sides):
    print("Side:",z+1)
    print("Input the Coordinate:")
    x = int(input('Input Coordinate x:'))
    y = int(input('Input Coordinate y:'))
    cord_data.append(x)
    cord_data.append(y)
print("\nArea of the Polygon:",poly_area(cord_data))

Sample Output:

Input number of sides:  5
Side: 1
Input the Coordinate:
Input Coordinate x: 1
Input Coordinate y: 0
Side: 2
Input the Coordinate:
Input Coordinate x: 0
Input Coordinate y: 0
Side: 3
Input the Coordinate:
Input Coordinate x: 1
Input Coordinate y: 1
Side: 4
Input the Coordinate:
Input Coordinate x: 2
Input Coordinate y: 0
Side: 5
Input the Coordinate:
Input Coordinate x: -1
Input Coordinate y: 1

Area of the Polygon: 0.5

Flowchart:

Python Code Editor:

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