How to calculate the area of a curved line?

I have a bench which I have drawn in CAD, and I want to calculate the area.

The bench is a sort of "S" shape.

In the past I have only calculated the areas of straight objects and so have been able to pick points, but i'm not sure how to go about it when the object includes a curve.

If anyone knows how to do it, or can link me to a thread which already talks about it, I would be very appreciative

Thanks

Try using the AREA command.

If you have difficulty with it, you may want to use the PEDIT command to JOIN all the lines,

then try the AREA command again.

I was able to calculate the area for the "S" shape by making the lines into a boundary and found the calculated area in the properties bar.

However now I have a more difficult object that I need the area of

I have tried using the same process as I did before, using the "boundary" command however it pops up saying "a closed boundary can not be determined"

I have gone through each intersection of points to make sure they are all connected properly and they are. When it highlights the broken links, i fix them and then they still remain.

Can anyone think of a way I can calculate the area?

You could try using the AREA command, after using PEDIT to JOIN them.

Or once they are joined look in the properties box for the area.

Use the MULTIPLE option in the PEDIT command, so that you don't need to select them individually.

Use FUZZ DISTANCE of 0, and click enter at the end of the PEDIT JOIN command string.

You might also want to use the CHANGE command, select PROPERTIES, ENTER,

then ELEVATION, ENTER, choose new elevation of whatever you want, then hit ENTER twice.

After you do that you may well be able to BOUNDARY, HATCH, or JOIN them.

I tried using the PEDIT command, and it linked all the lines together in the top right hand corner of my shape, but it wont work with my straight lines, so i cant link all the lines together to make one complete shape :S

why do I have the feeling this is a really simple task and I am failing miserably at it! hahaha

why do I have the feeling this is a really simple task and I am failing miserably at it! hahaha

My guess is that they are non-coplanar, and have different elevations.

The CHANGE command could fix that.

Perhaps you have some 3D polylines in there, but unlikely, since you would have

to have created them intentionally.

Are you at liberty to post the dwg?

If so, I am sure we could fix it in very short order.

Shape.dwg

didnt really want to post the drawing on here, only cause its for work.

but i copied across the shape im having trouble with into a new document and can post that

Good solution.

Your Z values were totally out of control, as I guessed.

All good now.

Shape.dwg

could that have been because I was working off a survey plan?

how can I fix my Z values for the future?

I will have alot more shapes to calculate very shortly, so i just want to be able to identify the problem so I can fix it myself

can't believe i forgot to say thank u for fixing that for me! really appreciate it!

could that have been because I was working off a survey plan?

how can I fix my Z values for the future?

 

I will have alot more shapes to calculate very shortly, so i just want to be able to identify the problem so I can fix it myself

In the attached images you will see a couple things that will help you .

One image shows the quick properties palette describing the lines shown on the screen.

They all have the start and end Z values as 0, so we know that they are coplanar,

and at elevation 0.

You should probably go into OPTIONS, and on the DRAFTING tab set your OBJECT SNAP options

to use the current Z value. In that way when you trace points they will generate

a flat polyline. I see no reason why you wouldn't want to create a single CLOSED polyline when tracing these survey points.

I do not do Civil or survey work, so there may be some strange reason, which I don't know.

Thank you so much for that!

In my original document I went through the lines and changed their Z values to all be 0, so then when I tried to PEDIT them it all worked and they are all linked now and an area can be calculated!

Thank you so much for your help with this problem! I have alot of areas to calculate and get cost estimates for, so knowing how to do this will be invaluable

Thanks again

You are very welcome, glad I could help you.

I trust that you are not selecting lines individually, but rather are choosing everything

and then selecting LINES in Properties or QUICK PROPERTIES and changing all

their start and end Z values in one swell foop.

if you are tracing and want to create a flat drawing, either change your OSNAP OPTION setting as previously shown,

or make one continuous polyline containing them all, as a 2D Polyline will always be coplanar when you create it.

......I may have been doing each line individually...haha

but i wont anymore thanks to your suggestion

thanks heaps again

Here are two related methods to draw 2D in a 3D drawing.

Keep Z Values at Current Elevation

Draw a 2D Line with LISP

You may also use the Flatten command or one of these MACROs applied to a Button to change your Z values to 0 after drawing.

Flatten Selection

^C^C_UCS;;_select \_move _p;;0,0,1e99;;_move _p;;0,0,-1e99;;

Flatten All

^C^C_UCS;;_move _all;;0,0,1e99;;_move _all;;0,0,-1e99;;

The Flatten command would, well, flatten the lines on the Z axis to 0.