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This website has been deprecated and exists as an archive only.

The TORTOISE website has been moved to https://tortoise.nibib.nih.gov.

For any information about TORTOISE generation V3.x.x, please refer to the new website.

Initial System Setup

The current release of TORTOISE requires linux or intel based Mac OSX. It runs with either an IDL license, or the IDL Virtual Machine (VM). The IDL VM is distributed with the software, so you do not need to install the IDL VM at this time.

If you need to, or wish to install IDL including the IDL VM, it can be downloaded from the ITT website http://www.ittvis.com. Detailed instructions on installation of the IDL VM can be found here: 1.3.4 IDL VM.

Download and untar the TORTOISE distribution tarball found on the TORTOISE DOWNLOAD page to any convenient location which does not contain spaces in the path. In the TORTOISE directory you will see 3 folders—DIFF_CALC, DIFF_PREP, and IDL71—as well as a readme and the license agreement. These contain the 2 TORTOISE modules and the pre-packed IDL VM respectively. A separate download is available containing sample data. No further installation steps are necessary!

When you first run DIFF_CALC and DIFF_PREP new folders will be created called DIFF_CALC_WORK and DIFF_PREP_WORK respectively, in your computer's home director. These directories are used for storing configuration and settings files, as well as for writing out log files and temporary files.

Running the software is described on the next page.