At the conclusion of many commands, the user is placed into the "Disposition Menu". In this menu, data may be processed and written to either an output file, a post-processing file, the terminal, a graphics device, or to a global variable.

When dealing with data in the Disposition Menu, it is best to think of it as being a matrix. The columns of the matrix are called variables and the rows are called records. Each variable is identified by its column number or name , and one can obtain a list of the names of the variables and their column numbers by issuing the command,


Throughout this menu, one selects columns with column selectors. These selectors can be a single number, a colon separated pair of numbers, or a name selector; e.g. 5, 7:8, @x:@. The colon pair selects all columns from the first number to the second one. In many cases, only a limited number of columns can be selected. In this case, the first one selected will be used. For example, suppose that you can select six values and you use 1:12 for the column selector, then only 1:6 will be used.

Sometimes, one may wish to alter the values of the data available. This can be accomplished by using either of the commands:

     C_SCALE, SCALE_F, CS(1),  CS(2), ...

     C_SHIFT, SHIRT_F, CS(1),  CS(2), ...

The C_SCALE command defines a multiplier by which a variable will be scaled, and the C_SHIFT defines a constant which will be added to the variable. Once of these factors are established, they will stay in effect until it is changed with a new C_SCALE or C_SHIFT command, or until the Disposition Menu is exited.