image thumbnail

inside triangle

version 1.0.0.0 (1.51 KB) by Nassim Khaled
inside_triangle is used to check if a point P is inside the triangle P1P2P3 or not.

2.7K Downloads

Updated 15 Jan 2009

View License

%inside_triangle is used to check if a point P is inside
%the triangle P1P2P3 or not.
%
%Inputs: P, P1, P2 and P3 are vectors of length 2 or three of the
% form [x y z] or [x y]
%
%Output: True
%True=1 => P is on or inside P1P2P3
%True=0 => P is outside P1P2P3
%
%Example:
%True=inside_triangle([0.5 0.5],[0 0],[0 2],[2 0]);
%
%The following algorithm is implemented
% If P is ON or INSIDE the triangle
%
% Area(PP1P2) + Area(PP2P3) + Area(PP3P1) = Area(P1P2P3)
%
% If P is OUTSIDE then,
%
% Area(PP1P2) + Area(PP2P3) + Area(PP3P1) > Area(P1P2P3)
%
% Area of a triangle can be found using the determinant:
%
% Area = abs(1/2 * |x1 y1 1| )
% |x2 y2 1|
% |x3 y3 1|
%

Cite As

Nassim Khaled (2021). inside triangle (https://www.mathworks.com/matlabcentral/fileexchange/22690-inside-triangle), MATLAB Central File Exchange. Retrieved .

MATLAB Release Compatibility
Created with R14SP1
Compatible with any release
Platform Compatibility
Windows macOS Linux

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!