What's New?

Feedback from users is very valuable to us in designing and improving NetLogo. We'd like to hear from you. Please send comments, suggestions, and questions to feedback@ccl.northwestern.edu, and bug reports to bugs@ccl.northwestern.edu.

Version 1.1 Rev D (August 2002)

• content:
  • fixed links in PDF version of User Manual that took you to the wrong page
  • the "Known Issues" section of the User Manual now lists a few more known bugs
  • improved models: Rabbits Grass Weeds (better default slider settings), Painted Desert Challenge (better default slider settings), CA 1D suite (faster, clearer code)
  • adjusted the interfaces of many models so that texts don't get cut off even on Java VMs with a large default font size
• engine fixes:
  • fixed slight periodic bias in random number generator when generating small integers
  • several fixes to in-radius: it now wraps around the edges, and handles radii larger than screen-edge-x/y properly, and no longer leaves out some turtles near the edge of the circle
  • fixed case where the compiler sometimes incorrectly interpreted parentheses inside brackets
  • fixed bug where turtle/patch labels in the bottom row of patches could cause Java exceptions while zooming
  • using shade-of? no longer causes an agent's turn to end
  • fixed several bugs in StarLogoT model converter
• interface fixes:
  • fixed bug where changes to the patch size weren't always saved with the model
  • fixed some cases where the Errors tab didn't always highlight the location of syntax errors correctly
  • fixed a bug where the Procedures menu could produce Java exceptions
  • printing the procedures and info tabs now uses a smaller font size
  • fixed Mac-only bug where the "Import Shapes" feature sometimes behaved strangely when choosing a model
  • fixed Linux/Unix only bug where trying to create or edit a plot made NetLogo grind nearly to a halt
  • fixed bug on Java 1.4 VM's where the Tab key didn't work in the Command Center and Procedures tab
  • now on Macs subsequent Java exceptions after the first are no longer lost
  • when running under Classic on OS X 10.2, the "User Manual" menu item on the Help menu now works, and launches your default browser instead of always Internet Explorer
  • when running native on OS X 10.2 (which is not officially supported yet), the Quit menu item now asks you if you want to save your changes, like it should
• fixes to "Save as Applet" feature:
  • improved instructions in saved applets, and made them visible HTML text instead of invisible HTML comments
  • saved applets now bring up runtime error dialogs on all systems when something goes wrong
  • saved applets now work when run from the local hard drive (as opposed to a web server), even on Mac OS X, and even on Windows if the model name has spaces in it

Version 1.1 (July 2002)

• content:
  • added "Frequently Asked Questions" section to User Manual
  • new suite of 1-dimensional cellular automata models: Cellular Automata 1D (an improved version of our old "Cellular Automata" model), CA 1D Totalistic, CA 1D Rule 30, CA 1D Rule 30 Turtle, CA 1D Rule 90, CA 1D Rule 110, CA 1D Rule 250
  • new model conversions: Koch Curve, Rumor Mill, Random Walk Left Right
  • new chemistry models: Crystallization Moving, Crystallization Directed
  • improved models: Crystallization Basic (formerly Solidification), Mouse Example (expanded), Tetris (bugfixes), Pac-Man (bugfixes), AIDS (bugfix, cleanup, clearer code), Traffic 2 Lanes (cleanup, clearer code)
• features:
  • "Save as Applet" (on the File menu) lets you embed your model in any web page
  • you can now print the contents of any tab on a printer
  • Procedures tab now has popup menu that lets you instantly jump to any procedure in your code
  • Interface tab is now scrollable
  • Interface tab now has "contextual" popup menus that let you create, edit, and delete interface elements, as well as open turtle and patch monitors; on Macs, control-click to bring up the menus, on other platforms, use the right mouse button
  • agent monitors are now their own floating windows; agent command centers now do syntax highlighting and support command history
  • code editor now auto-indents a new line to the same level as the line above it; arrow keys in combination with option key (Mac) or control key (other OS's) now moves word by word
  • tab key now cycles the Command Center between Observer, Turtles, and Patches
  • sliders now have an optional "units" field
  • performance improvements made so models run faster (most models only a little faster, but some substantially)
  • new turtle graphics options (note: using these options slows down most models a lot; we hope to improve this in a future version):
    • new turtle variable called size; edit the Graphics Window and check the "Turtle Sizes" checkbox to enable scaling of turtles according to this variable
    • new "Exact Turtle Positions" checkbox; edit the Graphics Window and check this box to enable drawing of turtles in their exact positions, instead of always in the center of their patch as is the default
• language changes:
  • new primitive without-interruption lets you mark a section of code as being executed all at once without any other agents being able to interrupt
  • new primitives neighbors and neighbors4 return an agentset of a turtle's or patch's eight (or four) neighboring patches
  • new primitive inspect lets you open an agent monitor for any turtle or patch
  • new primitives user-choice and user-input for accepting input from user
  • new primitive read-from-string for converting strings (e.g. user input or input from a file) into data
  • the and and or primitives now "short circuit", which means they no longer evaluate their right hand arguments unless necessary
  • message primitive renamed to user-message
• engine fixes:
  • fixed Windows-only bug where models that used plot-pen-reset a lot tended to crash NetLogo
  • the random primitive now works properly on negative integers and on zero
  • fixed bug in cct, hatch, and sprout where sometimes the new turtle was not initialized immediately
  • fixed bug where setting a turtle's x or y coordinate to an extremely large value could cause NetLogo to stop responding
  • fixed bug where editing screen-edge-x/y didn't empty the breed agentsets
  • the turtle and patch primitives now signal a runtime error if passed non-integer arguments
  • fixed compiler bug that could cause a confusing error message if you used an observer-only primitive in the same context as a turtle/patch-only primitive
  • fixed bug where sometimes patches containing only hidden turtles were drawn with an incorrect color
  • fixed bug where changing a label's color didn't always redraw the whole label immediately
  • using the double quote character (") in a plot pen name no longer confuses NetLogo
  • fixed rare bug where a runtime error could cause Java exceptions if it occurred inside a procedure where an agentset was stored in a local variable
• interface fixes:
  • now when you open a widget editor the contents of the default field are selected, and when you use the Tab key the contents of the next field become selected
  • fixed bug where occasionally button presses were ignored
  • now if you try to open a file that is not a valid NetLogo model, you get a warning instead of it just failing silently
  • fixed bug where monitors set to a very high number of decimal places (such as 20) sometimes had a slight rounding error
  • numerous fixes to sliders including:
    • fixed rounding errors where sliders could return slightly incorrect values (that differed from the correct values in the 15th decimal place or so)
    • fixed handling of various unusual values or combinations of values for minimum, maximum, and increment
    • appearance when zoomed is improved
• BehaviorSpace improvements:
  • added an "Export Plot" button and an "Export Behavior Data" button
  • improved behavior of plots with respect to using consistent axes across model runs
  • assorted small usability improvements
• HubNet improvements:
  • all six HubNet activities revised and improved
  • no more TI-83+ button -- login is initiated instead by the new hubnet-reset primitive
  • HubNet now supports receiving non-list data types including numbers, strings, and matrices
  • HubNet Programming Guide revised and expanded
  • all old HubNet primitives removed from language and replaced with new set of primitives: hubnet-reset, hubnet-message-waiting?, hubnet-fetch-message, hubnet-message, hubnet-message-source, hubnet-message-tag, hubnet-broadcast, hubnet-set-tags, hubnet-set-client-interface

Version 1.0 (April 2002)

• User Manual redesigned and expanded
• permanent plot pens
• miscellaneous fixes and improvements

Beta 10 (March 2002)

• models using turtle and patch labels run faster
• improved compiler and runtime errors and error handling
• usability improvements to Command Center
• full string processing capabilities
• plotting modes: line, bar, and point
• miscellaneous fixes and improvements

Beta 9 (December 2001)

• models run faster now
• syntax-highlighting editor
• new language support for working with agents individually
• "Import World"
• integer sliders
• Edit menu
• miscellaneous fixes and improvements

Beta 8 (October 2001)

• miscellaneous fixes and improvements

Beta 7 (September 2001)

• models that use turtle shapes now run much faster
• much larger numbers of agents now supported
• more colorful & attractive interface
• runtime errors
• "Zoom In" and "Zoom Out" for easy viewing
• histograms
• breed-specific turtle variables
• patch labels
• true integer arithmetic
• random-seed primitive for repeatable model runs
• miscellaneous fixes and improvements

Beta 6 (August 2001)

• Mac OS X support (in Classic environment)
• Models Library organized into categories, with screen shots
• language now supports turtle "breeds"
• BehaviorSpace, a tool for exploring the "space" of different ways a model can behave
• "Export World", "Export Plot", and "Export Output"
• local variables (locals keyword)
• "Find" and "Find Again" buttons in Procedures window
• HubNet can now send data to the teacher calculator
• miscellaneous fixes and improvements

Beta 5 (June 2001)

• models run much faster now
• collection of "Code Examples" added to Models Library
• agent monitors much improved
• miscellaneous fixes and improvements

Beta 4 (March 2001)

• greatly improved general stability & reliability
• web-based installer automates installation process
• runs as stand-alone application on all platforms
• shapes editor for turtle shapes
• miscellaneous fixes and improvements

Beta 3a (December 2000)

• miscellaneous fixes and improvements

Beta 2 (October 2000)

• miscellaneous fixes and improvements

Beta 1 (September 2000)

• first public beta release