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'Logo' printed from http://nrich.maths.org/

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Commands roughly follow MSWLogo syntax, so until we have a complete help system, please use the MSWLogo help for deeper explanations.

Command names are case insensitive.
e.g. 'print', 'PRINT, and 'Print' are all equivalent.

Here is the list of Logo commands that are currently supported in some shape or form.

+ - * / = < > abs arccos arcsin arctan back bk butfirst butlast clearscreen cos cs difference empty equalp exp first forward fd fput greaterp halt heading hideturtle ht if ifelse int item last left lessp list ln log10 lput make member minus pd pendown penup pi power print product pu quotient radarccos radarcsin radarctan radcos radsin radtan repeat right run sentence setpc setpencolor setpencolour setpensize setspeed setx setxy sety show showturtle sin speed sqrt st sum tan trace untrace wait word xpos ypos

The demonstrator starts with the editor already containing a working program. Press Run to test this. You should see it output to both the turtle graphics window and the output window.

To enter your own program, clear the editor panel and type it in. Use 'Revert' to restore the demonstration program.

In this version you may save a copy of one program using the Save button. This will be restored to the editor panel when you press Load. The code is stored on your computer so Load will only restore a program you saved earlier using the same machine.

If you want to save a program into a file, you can do so by selecting the text, then Right-Click > Copy. Paste the result into any text editor and save. You can use something like Notepad, Word, TextEdit for this last step.

To reload a program saved in this manner, simply paste the text back into the editor box with Right-Click > Paste.

Window panels can be moved, minimised, and resized. To illustrate different problems we can configure these panels appropriately and seed the editor with some initial logo code.

Differences from MSWLogo
  • SETSPEED sets the turtle animation speed. It needs a number between 1 and 10. SPEED returns the current turtle speed.
  • Just one turtle is allowed
  • The turtle can only move in 2D space.
  • We don't plan to support BURY and related commands, functional programming constructs (APPLY, YIELD, MAP,...), exception handling with THROW and CATCH, legacy Windows colour palettes and patterns, Logo generated user controls (RADIOBUTTONCREATE,...)
  • The following will be supported only if needed: the ARRAY data type, BITMAPTURTLE
  • These can never be supported due to the limitations of Flash and/or online delivery: File I/O, 3D, POLY commands (POLYSTART,...), access to MIDI devices, Mouse I/O.