

Planimeter - gballan
http://en.wikipedia.org/wiki/Planimeter

======
dTal
It is not intuitive to me why this works, which is very exciting because it'll
be fun when I "get it". Is there somewhere online that explains it in an
intuitive way?

~~~
gballan
I don't get it either. Tell you what -- I'll put something together and post
to HN. (Will take a couple of weeks or so.)

~~~
theoh
It's similar in principle to the algorithm described here:
[http://www.mathsisfun.com/geometry/area-irregular-
polygons.h...](http://www.mathsisfun.com/geometry/area-irregular-
polygons.html)

Prytz (hatchet) planimeters are more tricky and approximate in the way they
work.

------
acomjean
I used one as a civil engineer to estimate quantities of cut and fill from
plans. They are quite amazing tools.

