### Author Topic: Need help to convert this equation.  (Read 1673 times)

0 Members and 1 Guest are viewing this topic.

• Swamp Rat
• Posts: 1352
##### Need help to convert this equation.
« on: May 21, 2012, 09:56:10 AM »
I tried to convert these equations to use in lisp but giving me diffident results than Excel.
Could some one help me to convert this equations to use in Lisp?

Thanks

• Swamp Rat
• Posts: 1352
##### Re: Need help to convert this equation.
« Reply #1 on: May 21, 2012, 10:08:17 AM »
This is input
Code: [Select]
`(and (setq p1 (getpoint "\nPick first point."))    (setq p2 (getpoint p1 "\nPick second point."))    (setq *L* (cond ((getint (strcat "\nWhat is HIGH Point <" (itoa (setq *L* (cond ( *L* ) ( 160 )))) ">: "))) ( *L* )))    (setq *c* (cond ((getint (strcat "\nWhat is LOW Point <" (itoa (setq *c* (cond ( *c* ) ( 35 )))) ">: "))) ( *c* )))    )(setq step 1000 dist (distance p1 p2) #pt (fix (/ (/ dist step) 2)) ang  (angle p1 p2) pang (+ ang (/ pi 2.)) idx  1    )`
Equation
Code: [Select]
`(setq S  (* 0.8 Dist);    X  (* idx step)    a1 (/ (* (* (- *L* *c*) 0.1) Dist) (/ Dist 2));    ys1 (- *L* a1);    A  (/ (- *c* ys1) (- (/ (* S S) 4) (/ (* S S)2)));    B  (- 1 (* A S));    y  (+ (+ (* A (* X X)) (* B X)) ys1)    yr (round y 5)      )`

#### Keith™

• Villiage Idiot
• Seagull
• Posts: 16897
• Superior Stupidity at its best
##### Re: Need help to convert this equation.
« Reply #2 on: May 21, 2012, 10:13:04 AM »
You have to calculate the variables used in later calculations first.
Proud provider of opinion and arrogance since November 22, 2003 at 09:35:31 am

Find me on https://parler.com @kblackie

• Swamp Rat
• Posts: 1352
##### Re: Need help to convert this equation.
« Reply #3 on: May 21, 2012, 11:33:43 AM »
You have to calculate the variables used in later calculations first.

Is it OK
Code: [Select]
`(setq Dst2 (/ Dist 2) S   (* 0.8 Dist) SS  (* S S) SS2 (/ SS 2) SS4 (/ SS 4) S42 (- SS4 SS2) X   (* idx step) XX  (* X X) XXA (* A XX) XB  (* B X) XAB (+ XXA XB) Lc  (- *L* *c*) Lc1 (* Lc 0.1) LcD (* Lc1 Dist) a1  (/ LcD Dst2) ys1 (- *L* a1) yc  (- *c* ys1) A   (/ yc S42) B   (- (* A S)) y   (+ XAB ys1) yr  (round y 5) )`