The quantities in the .spd, .gbs and .opt files are units dependent. In order to provide the greatest generality, the MIT supports units conversion. Units conversion is necessary for two scenarios:

 

Managing Units Conversion

The image below summarizes how MIT manages units conversions:

The MIT first checks to see whether the Input .spd and the Input .gbs/.opt have the same units. If the MIT detects a units mismatch, the MIT creates a new version of the Initial .gbs and .opt files that have the same units as the .spd file. The Fitting Tool then operates in the units of the .spd file and generates an Output .spd file using the same units as the Input .spd file. The fitting tool also generates an internal fitted .gbs file. This .gbs file uses the same units as the .spd file.

During the .gbs export operation, you have the option of specifying a set of units for the Output .gbs file. If these units are different from the ones in the Input .spd file, the MIT converts the internally generated Output .gbs file to the desired set of units, and then writes out the file.