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First solution in Uncategorized category for Area of a Convex Polygon by kvas
def det(p1, p2):
(x1, y1), (x2, y2) = p1, p2
return x1 * y2 - x2 * y1
def checkio(data):
return abs(sum(det(p1, p2) for p1, p2 in zip(data, data[1:] + data))) / 2
#These "asserts" using only for self-checking and not necessary for auto-testing
if __name__ == '__main__':
assert checkio([[1, 1], [9, 9], [9, 1]]) == 32, "The half of the square"
assert checkio([[4, 10], [7, 1], [1, 4]]) == 22.5, "Triangle"
assert checkio([[1, 2], [3, 8], [9, 8], [7, 1]]) == 40, "Quadrilateral"
assert checkio([[3, 3], [2, 7], [5, 9], [8, 7], [7, 3]]) == 26, "Pentagon"
assert checkio([[7, 2], [3, 2], [1, 5],
[3, 9], [7, 9], [9, 6]]) == 42, "Hexagon"
assert checkio([[4, 1], [3, 4], [3, 7], [4, 8],
[7, 9], [9, 6], [7, 1]]) == 35.5, "Heptagon"
May 23, 2013
