mathtools/internal/lib/shoelace.go

34 lines
888 B
Go

/*
Copyright © 2025 filifa
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package lib
type Point struct {
X float64
Y float64
}
func Area(points []Point) float64 {
total := float64(0)
n := len(points)
for i, p := range points {
q := points[(i+1)%n]
total += (p.Y + q.Y) * (p.X - q.X)
}
return total / 2
}