Hi Rob,
Assuming (X1,Y1), (X2,Y2),(X3,Y3),.....(Xn-2,Yn-2),
(Xn-1,Yn-1),(Xn,Yn) are your coordinates in Cartesian domain, your area
function would be as follow:
2x Area = X2Y1 + X3Y2 + X4Y3 + ...+YnYn-1 + X1Yn - X1Y2 - X2Y3 - ... -XnY1
Thus, Area = RHS / 2 unit square.
Good luck.
Regards,
Michael
At 16:41 12-03-02 +1000, Robert Crossley wrote:
>Can anyone point me in the direction of a formula or technique to
>calculate an area of irregular shapes (no holes), from a
>list of coordinates - without a GIS? The answer can be in square
>coordinate units. The formulae uncovered so far
>indicate a rather manual subdivision of the shape into triangles, but I
>suspect that this is not the only answer.
>
>I know that this is not a Mapinfo question, but it is a geographic question.
>
>Thanks
>Rob.
>
>
>----------------------------
>Robert Crossley
>Robert Crossley and Associates
>9 Short Street
>NEW BRIGHTON NSW Australia 2384
>
>P: 61-2-66801309
>F: 61-7-????????
>M:0419718642
>GPS: ?????
>----------------------------
>
>
>
>
>_______________________________________________________________________
>List hosting provided by Directions Magazine | www.directionsmag.com |
>To unsubscribe, send e-mail to [EMAIL PROTECTED] and
>put "unsubscribe MapInfo-L" in the message body.
-------------------------------------------
Schlumberger
Michael Tang
Senior Technical Engineer
Oslo Technology Center
Solbraveien 23
Asker, N-1372
Office: (47) 6678-8338
Fax: (47) 6678-8503
-------------------------------------------
[EMAIL PROTECTED]
-------------------------------------------
_______________________________________________________________________
List hosting provided by Directions Magazine | www.directionsmag.com |
To unsubscribe, send e-mail to [EMAIL PROTECTED] and
put "unsubscribe MapInfo-L" in the message body.
