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First Forward Into Logo 1: Square Five

A Short introduction to using Logo. This is the first in a twelve part series.

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LOGO Challenge 1 - Star Square

Can you use LOGO to create this star pattern made from squares. Only basic LOGO knowledge needed.

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LOGO Challenge 5 - Patch

Using LOGO, can you construct elegant procedures that will draw this family of 'floor coverings'?


Stage: 2, 3, 4 and 5 Challenge Level: Challenge Level:1

Release Notes
Version 0.6
  1. Ran regression tests again and discovered that v0.5 had indeed regressed due to problems with returning values from procedures. v0.6 fixes these.
  2. Boolean and Logical operations should be added
  3. Next release should adddress the two major problems of infix operator precedence and better handling of recursion depth. A new tokeniser is in the works for this.

Version 0.5
  1. Added Pause/Resume to Output panel too.
  2. New primitives: abs arccos cos radarccos radcos arcsin sin radarcsin radsin arctan tan radarctan radtan exp ln log10 pi power sqrt setspeed speed
  3. show and print nowunderstand parenthesised calls as in (show 1 2 3 4 "five), which displays the list [1 2 3 4 five]
  4. Fixed a race bug in turtle animation
  5. Added support for comments . These start with a semicolon and continue to the end of line.
  6. Added numeric range checking to primitive calls. e.g. (arccos -2) will print 'arccos doesn't like -2 as input'.

Version 0.4
  1. Turtle movements are now animated so you can see them happening.
  2. Added Turtle speed control. The fastest speed (10) skips the animation.
  3. Added Pause/Resume button
  4. Fixed bug in 'left'

Version 0.3
  1. Fixed Run button behaviour

Version 0.2
  1. (sum 1 2 3) and (product 1 2 3 4) now work. Note that (+ 1 2 3) returns a syntax error because + is an infix operator. (1 + 2 + 3) is the equivalent syntax for +. (* is similar)
  2. Print and Show now mirror MSWLogo behaviour correctly
  3. There needs to be a separate command panel
  4. Need Single Step
  5. Hitting the Run button while the program is running confuses it.

Version 0.1
  1. Operator precedence is not supported yet. Use parenthesis. e.g. (2*3)+4
  2. The code reader does not distinguish unary minus (negative numbers) from binary subtraction well and can get confused. Use parenthesis.
  3. Recursion is only supported to a depth of 255 calls.
  4. Load and Save only allow you to save one program
  5. There is no inbuilt help system yet
  6. (sum 1 2 3) only sums 1 and 2
  7. Quite a few primitives are still missing