TheSwamp

Code Red => AutoLISP (Vanilla / Visual) => Topic started by: JohnK on January 05, 2005, 10:09:27 AM

Title: (Challange) Interpolate
Post by: JohnK on January 05, 2005, 10:09:27 AM

This challange is to interpolate between two knows situations and return the third unknown value. For instance:

Key -- Value
--------------
20  --  2400
28  --  3200

Find the value for the key 24 and return it to me.

Title: (Challange) Interpolate
Post by: whdjr on January 05, 2005, 10:19:41 AM

24 = 2800

Title: (Challange) Interpolate
Post by: Keith™ on January 05, 2005, 10:27:18 AM

I got my answer ....

Title: (Challange) Interpolate
Post by: JohnK on January 05, 2005, 10:36:57 AM

So when do you think we can start posting our solutions? (What did we decide that one time we were talking about submitting lisp to these challanges.)

Title: (Challange) Interpolate
Post by: Mark on January 05, 2005, 10:47:21 AM

Well I'd give it a few hours any way.

Title: (Challange) Interpolate
Post by: Keith™ on January 05, 2005, 10:49:41 AM

dunno ... it is your thread ...

Title: (Challange) Interpolate
Post by: JohnK on January 05, 2005, 10:58:25 AM

Okay, a few hours it is then.

Give 'er two hours.

Title: (Challange) Interpolate
Post by: whdjr on January 05, 2005, 10:58:57 AM

I thought we said it was up to the original poster of the question.
Hence no directions so I didn't hold back.

Title: (Challange) Interpolate
Post by: whdjr on January 05, 2005, 10:59:52 AM

I guess I was too early AND too late.

Title: (Challange) Interpolate
Post by: JohnK on January 05, 2005, 11:02:09 AM

lol ...No your lisp. You can post the answer. The  answer is not that hard to achieve.

Title: (Challange) Interpolate
Post by: SMadsen on January 05, 2005, 11:58:13 AM

So, you want a linear or a weighed interpolation? What if the values looked like this?

20 -- 2400
28 -- 3200
30 -- 3205

Title: (Challange) Interpolate
Post by: JohnK on January 05, 2005, 12:06:44 PM

ummm... yes!

:shock: :P

Actualy, I just made mine to handle linear, but if you got one for weighted, thats extra cool!

Title: (Challange) Interpolate
Post by: Keith™ on January 05, 2005, 12:21:54 PM

Ok ...2 hours are up .....

Code: [Select]

(defun interpolate ( @k1 @v1 @k2 @v2 @N )
  (+ @v1(*(/(- @v2 @v1)(- @k2 @k1))(- @N @k1)))
)


Syntax:
(interpolate Key1 Value1 Key2 Value2 UnknownKey)

Title: (Challange) Interpolate
Post by: JohnK on January 05, 2005, 01:11:44 PM

mine too.  ...Wow same one. (Well i guess that was to be expected. Its just a formula after all huh?!)

Code: [Select]

;;;
;;; Example:
;;; 20  --  2400
;;; 28  --  3200
;;; Find the value for: 24
;;; (interpolate 20 2400 28 3200 24)
;;; -> 2800
(defun interpolate (n1 v1 n2 v2 n3)
  (+ (* (/ (- v2 v1) (- n2 n1)) (- n3 n1)) v1))

Title: (Challange) Interpolate
Post by: whdjr on January 05, 2005, 01:29:07 PM

hm... no formula here.  Just logic.  24 is halfway between 20 and 28, so 2800 is halfway between 2400 and 3200.  :D

Title: (Challange) Interpolate
Post by: JohnK on January 05, 2005, 09:45:47 PM

So you dont think you just followd a formula?

Title: (Challange) Interpolate
Post by: whdjr on January 06, 2005, 09:50:01 AM

hm...I guess so. :D