General HydroStatics
Ship Stability Software
Command of the Week
(New or interesting aspects of GHS that you may not know about)


There has been some confusion about GHSX, and not just on the part of John Bonn who wanted to buy a license for it. It seems John has a little time now after the completion of his big project, and he thought it would be a good time to delve into this "extended" GHS and learn what it could do for him.

For Mr. Bonn and anyone else who is interested, here are some facts about GHS vs. GHSX:

1. The computer codes that form GHS are of three types: GHS modules, GHSX modules, and "neutral" modules. ("Modules" here refers to computer-code modules, not the programs or features licensed as optional modules.)

2. Code Modules are linked in various ways to make the programs (.EXE files) collectively known as GHS.

3. GHSX-code modules are used to build Part Maker (PM/PMX), Section Editor (SE/DISPLAY), Condition Graphics (CG), Tank Soundings Extended (TSX), Grain Shift (GS), and Model Converter (MC).

4. GHS-code modules are used to build everything else. This includes the GHS main programs (GHS, GLM, BHS) and their native optional modules such as Load Editor (LE), Longitudinal Strength (LS), Floodable Lengths (FL), Tank Soundings (TS), Advanced Features (AF), and Multi-Body (MB).

5. Neutral modules are written in such a way that they can be linked with either GHS or GHSX code. For example, templates are implemented in a neutral module. This allows the TEMPLATE command to appear both in GHS and in GHSX-based products such as PM/PMX, TSX, and GS.

6. Additionally there are the two "command languages" of GHS and GHSX. Most wizards are written in the GHS command language, but those that deal with geometry typically depend on the GHSX command language.

7. Some products, notably Crane and Sensor Interface (SI), are implemented in the GHS command language. Even individual commands can be coded that way (the Advanced-Features STABILITY command is an example). TSX and GS have user interfaces written in the GHSX command language.

Note: All modules and wizards are accessed through the GHS main program.

Since there is no separate product on the price list called GHSX, we told John Bonn that if he wanted to explore what the GHSX command language has to offer, he could look at the library files that come with TSX and GS. These have long been available and open for users to examine and even modify or extend if desired. The RECOVER command will be found there, so it turns out that it was not a complete secret. Other examples of GHSX command language appeared in COW #16 and COW #38.

Questions, comments, or requests?
Contact Creative Systems, Inc.

USA phone: 360-385-6212 Fax: 360-385-6213
Office hours: 7:00 am - 4:00 pm Pacific Time, Monday - Friday

Mailing address:
PO Box 1910
Port Townsend, WA 98368 USA

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