Topographica is used in current research, and as such it can change quickly. Sometimes changes are made that render existing code obsolete in some way. This usually manifests itself in two ways: the first is that old snapshots can contain out-of-date code, and the second in that old scripts can contain out-of-date code.
Old snapshots should be supported automatically; if you find you have an old snapshot that will not load in a newer version of Topographica, please let us know by filing a bug report.
Old scripts can be supported by starting Topographica with legacy support (i.e. by passing -l to Topographica at startup). Usually, however, it is better simply to update the script, so that Topographica does not need to be used with legacy support (which is not as well tested as current code). For some versions, we provide a utility to update scripts to run with newer versions, though it is not guaranteed to convert every script properly, and isn’t available for all versions.
To update a script (e.g. /home/user/my_script.ty) written for 0.9.4, first update to 0.9.5 as described below.
To update your script from 0.9.5, change to your topographica/ directory, e.g.:
$ cd /home/user/topographica
and run the update utility:
$ etc/update_095_to_096 /home/user/my_script.ty
This will produce a new script, /home/user/my_script.ty_0.9.6, which should run on the latest version of Topographica. Some of the changes will require manual editing, e.g. to fix the numbers of parentheses in some expression, but these should be relatively simple to correct in the .ty file.
If you find the script still will not run, please file a bug report so that we can fix the problem. (To work with your original script immediately, you can instead try running Topographica with legacy support enabled, as described earlier.)
To update a script (e.g. /home/user/my_script.ty) written for 0.9.4, first change to your topographica/ directory, e.g.:
$ cd /home/user/topographica
Then run the update utility:
$ etc/update_094_to_095 /home/user/my_script.ty
This will produce a new script, /home/user/my_script.ty_0.9.5, which should run on the version 0.9.5 of Topographica.
Currently, we do not explicitly support code written for versions of Topographica prior to 0.9.4. Depending on the age of the code, though, such support is possible in theory. Please let us know if you have an old script (or snapshot) that you need to use in a modern version of Topographica.