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A few years ago, I built an elliptical stairway for Illinois congressman Tim Johnson near Champaign, Il. When I went to the jobsite for the measurements, at that time I did not have a formulae for finding the length of the perimeter of an ellipse. I had to go back to my shop and make one of those jigs to draw out the full scale ellipse on the floor so that I could measure the run and finish laying out this stairway. Well necessity is the mother of invention, and I dug until I found a formulae for finding the length of an ellipse. Anyway, this formulae was followed by an asterick that said ” gives approximate length”. This formulae was off enough to force me to look further. I found no other formulae that helped me. I then modified this formulae by adding a clause to this formulae. I feel I have it real close now. I don’t want to post this formulae as I feel it will be the first one to come up anyway. Then I am wanting to show what I found wrong with this formulae, and what I added to it to make it much more accurate. I am confident you guys will come up with something better than what I have now modified. OK guys, I need the best formulae for the perimeter length of an ellipse. Note: It must pass the test of x/y ratio of 1:1 throught infinity:1
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A few years ago, I built an elliptical stairway for Illinois congressman Tim Johnson near Champaign, Il. When I went to the jobsite for the measurements, at that time I did not have a formulae for finding the length of the perimeter of an ellipse. I had to go back to my shop and make one of those jigs to draw out the full scale ellipse on the floor so that I could measure the run and finish laying out this stairway. Well necessity is the mother of invention, and I dug until I found a formulae for finding the length of an ellipse. Anyway, this formulae was followed by an asterick that said " gives approximate length". This formulae was off enough to force me to look further. I found no other formulae that helped me. I then modified this formulae by adding a clause to this formulae. I feel I have it real close now. I don't want to post this formulae as I feel it will be the first one to come up anyway. Then I am wanting to show what I found wrong with this formulae, and what I added to it to make it much more accurate. I am confident you guys will come up with something better than what I have now modified. OK guys, I need the best formulae for the perimeter length of an ellipse. Note: It must pass the test of x/y ratio of 1:1 throught infinity:1