CAD Forum discussion (EN) : Help with 3DPlot https://www.cadforum.cz/forum_en/ Wed, 10 Jun 2026 16:07:12 +0000 Tue, 17 Jul 2012 09:36:40 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 12.04 360 https://www.cadforum.cz/forum_en/RSS_post_feed.asp?TID=8020 <![CDATA[CAD Forum discussion (EN)]]> https://www.cadforum.cz/forum_en/forum_images/web_wiz_forums.png https://www.cadforum.cz/forum_en/ <![CDATA[Help with 3DPlot : Hi,your function definition is...]]> https://www.cadforum.cz/forum_en/forum_posts.asp?TID=8020&PID=20935&title=help-with-3dplot#20935 Author: Vladimir Michl
Subject: 8020
Posted: 17.Jul.2012 at 09:36

Hi, your function definition is not properly formated in AutoLISP syntax. Assuming you want to draw Z = cos(x) + sin(x), the proper syntax is:
 
(defun myFunc (x y) (list x y (+ (cos x) (cos y))))
 
This will draw a part of a 3D sphere.
]]> Tue, 17 Jul 2012 09:36:40 +0000 https://www.cadforum.cz/forum_en/forum_posts.asp?TID=8020&PID=20935&title=help-with-3dplot#20935 <![CDATA[Help with 3DPlot : Hi I am pretty new to AutoCad...]]> https://www.cadforum.cz/forum_en/forum_posts.asp?TID=8020&PID=20653&title=help-with-3dplot#20653 Author: joefromhersey
Subject: 8020
Posted: 24.Jun.2012 at 02:37

Hi I am pretty new to AutoCad and need some help plotting 3D surfaces from mathematical functions. I downloaded the 3DPlot utility and followed the instructions from this site: http://www.cadstudio.cz/en/apps/3dplot/.

I defined a shape myFunc using:
(defun myFunc (x y) (list x y (cos(x)+cos(y))))

However when I try to plot using:
(3DPlot myFunc -1.0 1.0 0.1 -1.0 1.0 0.1)

I get this error:
error: bad function: -1.0

What am I doing wrong? Also would it be possible for me to get repeating units of the function cos(x)+cos(y)?

]]> Sun, 24 Jun 2012 02:37:04 +0000 https://www.cadforum.cz/forum_en/forum_posts.asp?TID=8020&PID=20653&title=help-with-3dplot#20653