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+--- Thread: (48) Shoelace Method For Determining A Polygon's Area (/thread-11048.html)
(48) Shoelace Method For Determining A Polygon's Area - gerry_in_polo - 07-14-2018 03:12 AM
Shoelace Method for determining the area enclosed by any polygon. Enter the (X,Y) coordinates of the N polygon corners in a 2xN matrix and run the program. Example enter the following matrix of (X,Y) coordinates:
[[2 5]
[7 10]
[12 20]
[8 12]
[4 3]]
The polygon area calculated by the program is 10.5
RE: (48) Shoelace Method For Determining A Polygon's Area - Thomas Klemm - 07-14-2018 09:39 AM
This program works as well for the HP-48:
Code:
\<<
DUP HEAD +
2 \<< CROSS \>> DOSUBS
\GSLIST ABS 2 /
\>>However the pair of coordinates are expected in a list.
Example:
{
[ 2 5 ]
[ 7 10 ]
[ 12 20 ]
[ 8 12 ]
[ 4 3 ]
}
Area = 10.5