Which version of Turtle Art are you using? If you use the experimental fork, TurtleArtPortfolio, I think you'll find that the math functions are a bit more deterministic. Also, you can define as many variables and procedures as you'd like. (http://sugarlabs.org/wiki/images/7/78/TurtleArtPortfolio-12.xo)
You may also want to look at Tony's blog (http://tonyforster.blogspot.com/2009/02/using-insert-function-block-in.html) regarding defining functions on the fly. FInally, there is a largely undocumented feature that allows you to program the action of a block using Pippy. Try editing tamyblock.py (you'll find it in the Journal after you have first run TurtleArtPortfolio). Edit it in Pippy and then import it back into TurtleArtPortfolio using the Pippy button on the Save/Load tab. good luck. -walter On Sat, Feb 7, 2009 at 8:13 AM, Paul Schulz <pschul...@gmail.com> wrote: > Hi Everyone.. > > On Sat, Feb 7, 2009 at 10:27 PM, Bill Kerr <billk...@gmail.com> wrote: >> http://tonyforster.blogspot.com/2009/02/using-insert-function-block-in.html >> >> Tony Forster has used Walter's new insert function block in turtle art to >> program an analog clock > > I have been playing with TurtleArt with the aim of producing some > physical 2D models of forces on an object (the turtle). > > I have had some initial success: > - with x and y velocity being stored in box1 and box2 > ..constant force problems can be done. eg. > * projectile turtle > * charged turtle in a constant electic field > ..1D position related forces > * bouncing turtle > > I would like to model inverse square law motion as well (turtle in > space) but I hit a couple of problems. > > 1) I need 'braces' or I need to know more about the way that TurtleArt > calculates expressions.. > > eg. To calculate the new velocity I need something like.. > > new_vx = old_vx - constant * xpos / (xpos *xpos + ypos * ypos ) > > but I don't have braces '(', to delimit the denominator, and I am > already using box1 and box2 to hold the existing velocity components. > > 2) I though I could get away without it, but I also need the > 'sqrt' (square root) function. > > Also... > > As I'm not actually using the turtle to drew... I am using the 'moveto' the > new > location, I have to 'wiggle' the turtle (move forward and back) to make a > mark. > > - Is there another application I could use? > - How do I pull out my 'program' from sugar on my XO, for saving and sharing. > > Any help would be appreciated.. > > Cheers, > Paul > paul at mawsonlakes.org >> >> _______________________________________________ >> IAEP -- It's An Education Project (not a laptop project!) >> IAEP@lists.sugarlabs.org >> http://lists.sugarlabs.org/listinfo/iaep >> > _______________________________________________ > IAEP -- It's An Education Project (not a laptop project!) > IAEP@lists.sugarlabs.org > http://lists.sugarlabs.org/listinfo/iaep > -- Walter Bender Sugar Labs http://www.sugarlabs.org _______________________________________________ IAEP -- It's An Education Project (not a laptop project!) IAEP@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/iaep