**(To download the raw data files: Control click, or use,
go url "http:// theGivenLink" in the Rev msg box. Otherwise, just
click on the binary files.)**

- These stacks all presume that you have a copy of the application
*Runtime Revolutio*n. - You will find an evaluation edition at http://www.runrev.com/index_uk.html

## Four flavors of Turtle Graphics. Perhaps best understood by looking at the TG vocabulary.

Turtle graphics: This is the fastest, and most stable version. In includes many simulations in physics, biology and mathematics. It draws with the pencil.

Control turtles: This is used to do for controls what "Turtle graphics" does for the cursor (Turtle). It allows you to issue graphic commands to any control, button, field, graphic, or image. It uses vector graphics.

Tell turtles: Provides multiple turtles which draw independant vector graphics.

StopTurtles: Once again, provides multiple turtles and is vector based. This flavor of TG is best suited for applications which require a fast draw. See for example the Jack-in-the-box. In this mode the drawing does not evolve in time as it is drawn, but the graphic is set when the StopTurtle command is executed. Very fast. Something like the difference between a locked and unlocked screen, only faster.

Programming for science students. This text is not intended for those interested in a traditional computer science course. This is the sort of course which might be used to introduce science student to the basic tools in programming. It makes extensive use of Turtle Graphics, first on the theory that it allows for more interesting feedback to the beginning programmer, and secondly, it is a useful tool in generating graphic output of scientific results.This is a MS Word document.I am a retired physics professor, and, as you might imagine, many of the applications are related to my field of interest.It is based on a book I wrote some years ago titled:

Turtle Physics, Holt, Reinhart, and Winston, 1985. Also, in Spanish, Fisica con Logo, Hold, Reinhart, and Winston, 1985.

Utilities

Bezier Line (New and improved) This is a plug-in allowing you to paste a bezier line onto any card of any stack. It is the normal bezier curve you are probably familiar with, line and tangent controls. The line controls may be either corner points or continuous tangent points. The control points are made invisible by double clicking on the bezier line. (This gives you a single line with any shape compatible with the cubic parametric expansion of curve's function.) Double clicking again brings the control points back. It is self-contained. All handlers are in the control points and the bezier line itself. I have added the ability to remove all the bezier control and their scipts, thus reducing the overhead. It might reduce the size of your stack by 100 K or more. (In the compact version, you will have a choice of saving the bezier curve as an open line graphic or a closed polygon graphic.) A more compact version (40 K verser 180 K) of this plug in also available. (Acknowledgement: This is a extension of the very clever bezier stack of Alejandro Tejada, at http://www.geocities.com/capellan2000)

Colliding polygons: Determines when any two polygon graphics intersect.

Typing Superscripts and Subscripts Typing equations can be tiresome in Rev. This plug-in simplifies the process.

Manning Calculator Manning's equation allows one to predict how water flows in open channels. Given the coefficient of friction, the slope, the cross-sectional area and the wetted perimeter, one may calculate the water velocity, and from that the flow rate--volume per second. My interest in this arose from a local environmental issue. The local irrigation district was about to abandon or severely reduce the flow in a cherished neighborhood canal. One question was the expected water depth in the canal at various flow rates. This is a good example of the application of Bezier curves in Runtime Revolution.

Bouncing Ball Tools These tool deal with the interaction between a ball (graphic circle) and other graphic circles and bounding polygons.

Text to speech This app allow you to proofread text by clicking on any work and letting LC read from that point on.

CryptDivision.: Randomly chooses a 4 digit number and divides it into a 7 digit number. The result is encrypted and presented for you to decode. (This is the Mac version; for the Windows version download CryptDivisionCourier.rev)

Florida Ballot: What the Florida ballot might have looked like if a touch screen ballot had been used.

Cryptogram decoder: This is a utility for decoding cryptograms. For example if the encrypted word were ABCDBA and one knew that the letter C stood for the letter s then one would enter into the decoder: 12s*21. The decoder recognizes numbers as stand-ins for like letters, and the letter s for a known letter, and the asterisk for some unknown letter. The decoder shows, "gasbag" and "museum" as possible candidates for ABCDDBA where C stands for s.

Nine Ball Pool This is the traditional game of pool with nine ball. I have added spin (English) to allow the cue ball to rebound as it would in traditional poll when English is applied. Collisions between balls is a ssumed to be ideal, i.e. they conserve momentum and energy. (Thanks to Scott Rossi for his shinning graphics.)

Nine Ball with spin and undo Same as above but with undo, allowing you to repeat the last shot.

Daily Cryptogram This stack downloads the daily quotes from a web quotation page (The QuotationPage). These quotes are encripted with a simple letter-for-letter substitution. You job is to decode the quote. Included is the decoder mentioned above.

(These are all binary files.)

## Networks

In reading the book "Linked" by Albert-Laszlo Barabasi, I was startled by the statement: "When you add enough links such that each node has an average of one link, a miracle happens: A unique giant cluster emerges," a linked network evolves. This is a reference to a theorem of Paul Erdos on the theory of random graphs. Take N nodes; add N links between nodes; chances are that all the nodes are linked to one another. This stack was my attempt to verify this theorem.The Web is such a graph, a collection of web pages linked together. Other examples are the brain, a crystal, a body of cells, and group of acquaintances.