Autolisp making a trapezoid

[Anonymous]

Good day,

Please help me making a trapezoid using autolisp.

Length of Bottom, Height and Length at Top are the requirement.

Thank You.

[martti.halminen]

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@Anonymous wrote:

Good day,

Please help me making a trapezoid using autolisp.

Length of Bottom, Height and Length at Top are the requirement.

Thank You.

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Insufficient specification, there are  infinitely many  possible trapezoids fulfilling those requirements. You'll need to define additionally at least one angle.

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[CADaSchtroumpf]

Hi,

I suggest an old code (ten years ago!)

But for begin it's good base...

[Kent1Cooper]

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@Anonymous wrote:

....

Insufficient specification.... You'll need to define additionally at least one angle.

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... or, that it should be an isosceles trapezoid -- that would be enough information, if that's what is needed.

But I would also want to know:  The User should presumably be asked for some location point, which should be -- what?  The midpoint of the bottom edge?  The overall middle [halfway between the midpoints of opposite edges?  The lower left corner?  Something else?

In super-simple terms, with isosceles shape and the midpoint of the bottom as specified location:

(defun C:TRAPI (/ base bottom height top); = TRAPezoid, Isosceles
  (setq
    base (getpoint "\nMidpoint of bottom edge: ")
    bottom (getdist "\nLength of bottom edge: ")
    height (getdist "\nHeight: ")
    top (getdist "\nLength of top edge: ")
  ); setq
  (command "_.pline"
    "_none" (polar base pi (/ bottom 2))
    "_none" (polar base 0 (/ bottom 2))
    "_none" (polar (polar base (/ pi 2) height) 0 (/ top 2))
    "_none" (polar (polar base (/ pi 2) height) pi (/ top 2))
    "_close"
  ); command
); defun

[stevor]

Here is a start;

 ;  Ortho Symmetric Trapazoid   scg
 (defun C:OST (/ HBW HTW HPI P1 P2 P3 P4  BMP )
  (setvar 'osmode 0)(setvar 'orthomode 0)  
  (if (setq DBW (Get_d BBW "\n Base Width: ")
            DTW (Get_d DTW "\n Top Width: ")
            DTH (Get_d DTH "\n Top Height: ")
            BMP (getpoint  "\n Base Midpoint: ") ) ;  
    (progn
     (setq HBW (/ DBW 2)  HTW (/ DTW 2)  HPI (/ pi 2)
           P1  (polar BMP PI HBW)   P2 (polar BMP 0 HBW)
           PMT (polar BMP HPI DTH)
           P4  (polar PMT PI HTW)   P3 (polar PMT 0 HTW))
     (command "pline" P1 P2 P3 P4 "C")  
    ) (princ "Nyet "))  (princ))  
  ; DO:   ( C:OST )