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hawe		#1 Posted : 18 April 2020 15:27:08(UTC)
Rank: Advanced Member Groups: Registered Joined: 30/03/2020(UTC) Posts: 31 Location: KU Was thanked: 3 time(s) in 2 post(s)		Copy from one page to an other shows different behavior of sys P I know that eval will doctor (hello Jean :-) to the same result. but why is eval necessary in the second case und how can I see if eval is necessary?
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Jean Giraud		#2 Posted : 18 April 2020 16:30:50(UTC)
Rank: Guest Groups: Registered Joined: 04/07/2015(UTC) Posts: 6,866 Was thanked: 981 time(s) in 809 post(s)		Originally Posted by: hawe Copy from one page to an other shows different behavior of sys P Something in there does not cut the mustard. Attach the creator document to be copied on blank sheet Jean
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hawe		#3 Posted : 18 April 2020 17:07:02(UTC)
Rank: Advanced Member Groups: Registered Joined: 30/03/2020(UTC) Posts: 31 Location: KU Was thanked: 3 time(s) in 2 post(s)		the 2 versions of sys sys1.sm (24kb) downloaded 12 time(s). sys2.sm (30kb) downloaded 10 time(s).
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Jean Giraud		#4 Posted : 18 April 2020 18:28:12(UTC)
Rank: Guest Groups: Registered Joined: 04/07/2015(UTC) Posts: 6,866 Was thanked: 981 time(s) in 809 post(s)		Originally Posted by: hawe Copy from one page to an other shows different behavior of sys P Not same α° between the two documents ! Again: too specific rectangular construction of polygon. They are constructed from vertices coordinates. That was exemplified few days ago [Area, Perimeter, Centroid] Arc length on Engineering curve is partial perimeter, it goes in triplet [A,P,C]. Jean
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Jean Giraud		#5 Posted : 18 April 2020 19:11:20(UTC)
Rank: Guest Groups: Registered Joined: 04/07/2015(UTC) Posts: 6,866 Was thanked: 981 time(s) in 809 post(s)		The other conceptual pitfall is your rotation. rot(,) *[2*2] is commutative for only [2*2] systems [square/rectangle...] The universal code for XY longer than [2*2] ... XY*rot(,) If you don't follow this rule, Mathcad red, Smath error ...
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Jean Giraud		#6 Posted : 18 April 2020 22:54:47(UTC)
Rank: Guest Groups: Registered Joined: 04/07/2015(UTC) Posts: 6,866 Was thanked: 981 time(s) in 809 post(s)		Originally Posted by: Jean Giraud The other conceptual pitfall is your rotation. From there, you can compute [Area, Perimeter, Centroid] as per the "Maths Polygon" previously posted. As well for the native [full/reduced by list] as for the rotated of any angle. read NOT commutative Rotate Gerono.sm (15kb) downloaded 8 time(s).
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Jean Giraud		#7 Posted : 18 April 2020 23:41:53(UTC)
Rank: Guest Groups: Registered Joined: 04/07/2015(UTC) Posts: 6,866 Was thanked: 981 time(s) in 809 post(s)		Originally Posted by: Jean Giraud From there, you can compute [Area, Perimeter, Centroid] ... complete the tour [A,P,C] Rotate Gerono.sm (26kb) downloaded 10 time(s).
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overlord		#8 Posted : 19 April 2020 05:32:56(UTC)
Rank: Advanced Member Groups: Registered Joined: 23/07/2013(UTC) Posts: 1,128 Was thanked: 509 time(s) in 339 post(s)		Difference between two calculation occurs because of numeric and symbolic optimization. Just right click and select Optimization>Numeric for the copied formula in sys2.sm file This false flag happens a lot. Nothing is wrong here. As usual, the culprit is optimization. Regards
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hawe		#9 Posted : 19 April 2020 14:15:53(UTC)
Rank: Advanced Member Groups: Registered Joined: 30/03/2020(UTC) Posts: 31 Location: KU Was thanked: 3 time(s) in 2 post(s)		Originally Posted by: overlord As usual, the culprit is optimization. Regards Many thanks to hit the nuke of my question and many thanks to Jean for pointing out problems which I do not see in my limited perspective.
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