AREA command different output for object and perimeter points

Hi,

in CAD 2006 I'm using the AREA command on a polyline, and if i use area>o for object i get 3694 sf. If i use the AREA command on the SAME polyline, and i use area>first corner point and go around the perimeter of my polyline, i get 3399 sf.

Can anyone account for this nearly 300 sf difference?

Post a drawing file of this magical polyline. We are all a bit in the dark at the moment

pline.dwg

thanks- sure thing. Here is the file!

There is something weird about the way the pline was made. First I used Pedit, close and got an unexpected result. Then I exploded and re-joined everything and get a consistent area result.

If you List the Polyline, it says that it is Open, so the area shown with the Area command is not valid.

You could explode it, and then see where the doubling up of lines occurs. But if that is not something you want to do, the easiest way to get an area is to use Bpoly, and one sees that the area is 3398.2124 sq ft.

This solves it for me. Thank you so much. I will have to make sure that all my polylines are closed before calculating areas.

You will also have to make sure that you only have single lines, and that the start point and finish point are at the same point!

As the picture shows, there was an extra line of zero length at one corner, and the first (or last) three lines were duplicated.

I see. Eldon: would these extra lines and duplicate lines be deleted when i close my polyline? IOW, how do I eradicate these unintented extra and duplicated lines?

If you close your polyline, a line is drawn connecting the Start of the Polyline and the end. It does not delete duplicate lines. Even if you explode it, Pedit tries to use all the lines that have common end points.

It is much safer to make sure lines are not duplicated, or to use the Bpoly command.

In this situation, I might explode the polyline, then use Bpoly to make a proper closed polyline, and erase all the lines that made up the original polyline.

You might want to try the OVERKILL command. In theory this deletes duplicate lins (not sure about 0-length ones).

dJE