SL d a!     >START
SL d a!     .noop
SL d a!     f20  ;kg load hanging in the middle of the rope
SL d a!     (without f for fised the user is invited to enter another value) 
SL d a!     f35  ;m total length of the rope or wire
SL d a!     f2,5 ;m sag by load allowed
SL d a!     *SEIL (001)
SL d a!     .noop
SL d a!     (calculates only additional strength by weight, not the own weight of the rope.)
SL d a!     .noop
SL d a!     (Assumes straight ropes in a symmetric triangle)
SL d a!     .noop
SL d a!     (eg. for wire antenna calculations)
SL d a!     >END
SL           
SL          :SEIL
SL d a!     (weight len sag -- strength)
SL d a!     .2
SL d a!     .*
SL d a!     ./
SL d a!     (len*0.5 / sag)
SL d a!     .atan
SL d a!     (the angle is now on TOS in °)
SL d a!     .cos
SL d a!     .2
SL d a!     .*
SL d a!     .>R
SL d a!     .g
SL d a!     .*
SL d a!     (convert kg to Newton)
SL d a!     .R>
SL d a!     ./
SL d a!     (force in N)
SL          ;SEIL
COMPINDEX=      1
WB SEIL
