[MWForum]Re:snowflake

[Wendy Petti]

Walter, I beg to differ.  There are several ways to input starting values
of variables, and you and I have each selected a legitimate, different
method.  I chose to use sliders to supply the starting values.  You chose
to write a command followed by two numbers.  A third method would be to
enter the starting values into textboxes.  If the names of the textboxes
are LENGTH and LEVEL then the numbers written in the textboxes become the
values of these variables.

Of the three methods, I prefer sliders because there is then no way for the
user of the project to cause an error message, and there is no need for
typing in the command center.  For online projects, users can only
manipulate variables through sliders or textboxes.  They might not
understand what are suitable entries for a textbox.  But there is no way to
mess up the sliders.  I figure we might as well put the MicroWorlds objects
to good use!

It is true that the question marks in my code were unnecessary, but I
thought it might be confusing to use LENGTH for the name of a slider and
also for the name of a variable.  I was trying to make the point that in
the command:  SIDE LENGTH LEVEL, the value of the LENGTH slider becomes the
starting value for the LENGTH (or LENGTH?) variable, and the value of the
LEVEL slider becomes the starting value for the LEVEL (or LEVEL?) variable.
We could also use different variable names altogether so they bear no
resemblance to the sliders.  For instance, the slider names could be
STARTSIZE and STARTLEVEL (except I think only 8 characters of a slider name
are shown on the slider).

Wendy


-----Original Message-----
From: mwforum-admin@lists.mathcats.com
[mailto:mwforum-admin@lists.mathcats.com]On Behalf Of Walter Smith
Sent: Tuesday, July 15, 2003 3:05 AM
To: mwforum@lists.mathcats.com
Subject: RE: [MWForum]Re:snowflake


You are having problems with “variables” … length needs to be :length if it
is a variable … note the colon as the first letter of the word … that means
that it is really some number that can be changed … I removed the “?” there
is no questions as to what they are, they are stated when you run the
program such as “side 100 5” … the 100 is :length and 5 is :level …

Hope this helps … haven’t done this type of programs for a couple of years
as they closed out computer labs and I am now a kindergarten teacher … don’
t quite get this far with my kids in the year!

Walter

to koch_snowflake
seth -90
repeat 3 [rt 120 side :length :level]
end

to side :length :level
if :level = 0 [fd :length stop]
side :length / 3 :level - 1 lt 60
side :length / 3 :level - 1 rt 120
side :length / 3 :level - 1 lt 60
side :length / 3 :level - 1
end

-----Original Message-----
From: mwforum-admin@lists.mathcats.com
[mailto:mwforum-admin@lists.mathcats.com] On Behalf Of Mikula Family
Sent: Monday, July 14, 2003 10:50 PM
To: MW Forum Replies
Subject: [MWForum]Re:snowflake

When I run Wendy's following program:
to koch_snowflake
seth -90
repeat 3 [rt 120 side length level]
end
to side :length? :level?
if :level? = 0 [fd :length? stop]
side :length? / 3 :level? - 1 lt 60
side :length? / 3 :level? - 1 rt 120
side :length? / 3 :level? - 1 lt 60
side :length? / 3 :level? - 1
end
The message is ... I don't know how to length in koch_snowflake
Her demo on mathcats is perfect.  This is fun. Thanks for the help.