Known Issues
NetLogo 4.1 User Manual
If NetLogo malfunctions, please send us a bug report. See the
"Contacting Us" section for
instructions.
Known bugs (all systems)
Language/engine bugs
- The run and runresult primitives are often not
able to read or set variables created with let.
- Not all mathematical operations are checked, so it's possible
to get "Infinity" or "NaN" (Not a Number) as an
answer without a runtime error being signaled
- A bug in Java causes patch colors imported using import-pcolors to be
brighter than the original if the original image has a grayscale
palette. To work around this issue, convert the image file to an RGB
palette.
-
import-pcolors may
give slightly different results when running on Java 6 as compared
to Java 5.
Other bugs
- Out-of-memory conditions are not handled gracefully
- the "Snap to Grid" feature is disabled when zoomed in
or out
- Drawing and then erasing a line in the drawing may not erase
every pixel exactly.
- 3D graphics don't work on
some graphics configurations; on others 3D works but 3D full
screen mode doesn't.
- The size of the fonts used in a model's interface can vary
somewhat from computer to computer and from platform. As a result,
text that fits in a given space on one computer may not fit in
another. To avoid this problem, it is advisable to leave some extra
space in the sizes of buttons, sliders, etc.
- When running a model headless (from the command line), if the
model was created in an earlier NetLogo version, it may not work
properly. Use the GUI to open and resave the model in the current
NetLogo version before running it headless.
Windows-only bugs
- On some laptops, the Procedures and Info tabs may become garbled
when you scroll them. To avoid this bug, reduce the size of the
NetLogo window and/or reduce the color depth of your monitor (e.g.
change from 32-bit to 16- or 8-bit color). This is a bug in Java
itself, not in NetLogo per se. For technical details on the bug, see
http://developer.java.sun.com/developer/bugParade/bugs/4763448.html
(free registration required). NetLogo users are encouraged to visit
that site and vote for Sun to fix this bug.
Macintosh-only bugs
- When opening a model from the Finder (by double-clicking on it,
or dragging it onto the NetLogo icon), if NetLogo is not already
running, then the model may or may not open; the bug is intermittent.
(If NetLogo is already running, the model always opens.)
Linux/UNIX-only bugs
- We have discovered a problem on Linux where the "exp"
reporter sometimes returns a slightly different answer (differing
only in the last decimal place) for the same input. According to an
engineer at Sun, this should only happen on Linux kernel versions
2.4.19 and earlier, but we have observed the problem on more recent
kernel versions. We assume the problem is Linux-specific and does not
happen on other Unix-based systems. We are not sure if the problem
ever occurs in practice during actual NetLogo model runs, or only
occurs in the context of our testing regimen. The bug in the
Sun's Java VM, and not in NetLogo itself. We hope that only the
"exp" reporter is affected, but we can't be entirely
certain of this. NetLogo users are encouraged to visit
http://developer.java.sun.com/developer/bugParade/bugs/5023712.html
(free registration required) and vote for Sun to fix this bug.
- If NetLogo cannot find the font Lucida, menus will be illegible.
This has been known to happen on Fedora Core 3, after upgrading
packages. Restarting the X Font Server (xfs) has resolved the problem
in all reported cases.
Known issues with HubNet
See the HubNet Guide for a list
of known HubNet issues.