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

Cases in DB
(Requires GHS version 17.00 or later)

(Use the command DB Update to get the latest version of the Data Base software.)

In GHS Data Base terminology, "Case" refers to a set of weight elements.
There are fixed-weight cases of both the light-ship and non-light-ship variety and also tank cases.

Case is a convenient vehicle for storing and retrieving these three kinds of weights. Typically a light-ship case would be supplemented with a particular case of fixed weights plus a case of tank weights.

Of course the main advantage of separating weights into these three kinds is the ease with which they can be changed independently of one another. For example, it is easy to run through a series of tank cases for two or more fixed-weight cases.

Cases are stored under names that you assign. This is like writing tank settings or fixed-weights to a file and later retrieving them by running the file. The Data Base does something like that internally while making it more convenient for the user.

For example, DB PutFixWtCase "Departure Monday" stores the current fixed weights under that name.

As you would expect, DB GetFixWtCase "Departure Monday" retrieves the same set of weight items.

Cases are numbered too; therefore they can be retrieved either by name or number. The number lends itself to retrieval in a loop where the case is represented by an integer that is incremented in each cycle.

Case numbers are sequential; that is, they start with 1 and increment to the number of cases. Each of the three kinds of cases is independent of the others, and they all have their own series of numbers.

When you retrieve a light-ship case, all other fixed-weight items disappear. Therefore light ship must come first. After light ship has been established, it does not matter in what order any other fixed-weight items and tank settings are retrieved.

GetFixWtCase and GetLSWtCase when given without a parameter bring up a dialog which lists the cases and allows for changing their names. Here is an example from DB GetFixWtCase:

The case-number button retrieves the case. The button on the right examines the case, showing the weight items it represents:

The dialog from DB GetLSWtCase is quite similar.

The percentage applies to weights that have /MAX parameters in their definitions. If the weight has been deleted from the fixed-weight store, the status will say "missing".

Yes, the contents of weight cases are kept in the weight store and can be examined and edited with the DB EditLSWt/EditFixWt commands.

The Make Case of selected items button provides a convenient means of constructing weight cases.

The Examine Cases button shows a list of the cases.

DB GetTankCase was not forgotten. It belongs to another COW out in the field.

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

Click here for an index to this and previous COWs