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Diffstat (limited to 'sourcecodes/bnt-master/KPMtools/polygon_area.m')
| -rw-r--r-- | sourcecodes/bnt-master/KPMtools/polygon_area.m | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/sourcecodes/bnt-master/KPMtools/polygon_area.m b/sourcecodes/bnt-master/KPMtools/polygon_area.m new file mode 100644 index 00000000..43dffc77 --- /dev/null +++ b/sourcecodes/bnt-master/KPMtools/polygon_area.m @@ -0,0 +1,22 @@ +function a = polygon_area(x,y) +% AREA Area of a planar polygon. +% AREA(X,Y) Calculates the area of a 2-dimensional +% polygon formed by vertices with coordinate vectors +% X and Y. The result is direction-sensitive: the +% area is positive if the bounding contour is counter- +% clockwise and negative if it is clockwise. +% +% See also TRAPZ. + +% Copyright (c) 1995 by Kirill K. Pankratov, +% kirill@plume.mit.edu. +% 04/20/94, 05/20/95 + + % Make polygon closed ............. +x = [x(:); x(1)]; +y = [y(:); y(1)]; + + % Calculate contour integral Int -y*dx (same as Int x*dy). +lx = length(x); +a = -(x(2:lx)-x(1:lx-1))'*(y(1:lx-1)+y(2:lx))/2; +a = abs(a); |