A matrix, though you can choose it as a field "type" in the Field dialog, is not actually a field type itself, but a collection of two or more character fields whose exact position cannot be defined.
Do not confuse a matrix with indexed fields. Indexed fields are series of related fields with positions that can be defined exactly. You double-click or draw them one at a time and then fill in the Field dialog once for all of them.
A matrix of fields, on the other hand, is a group of fields whose position can vary within a defined area. (Click the links to examples below if you need a visual picture of what is meant by this.)
It is possible to define a character field containing more than one line of text without defining it as a matrix. Since that is a simpler solution, check first to see whether it would be a suitable solution before proceeding to define a matrix.
After you select Matrix as the field type and name the matrix, click the Matrix tab. Then choose a template from the list box. The choices, and an example of each, are:
Multiple lines is for lines of text. (Two examples)
Matrix is for a text arranged in lines and columns, a table. (Example)
Top + Matrix + Bottom is for a table-type format of data that is preceded and/or followed by one or more lines of data that are not to be interpreted. (Example)
Image filters cannot be applied.
Only character fields can be interpreted in a matrix. For example, no mark fields can be included unless Interpret is deselected for them.
The maximum number of lines is 140.
The maximum number of columns is 40.
There can be no vertical lines inside the boundaries of the field.
Horizontal lines thinner than 1.5 mm (about 1/16") are removed from character fields by the matrix interpreter.
The interpreter can correct text that is rotated max. 5 degrees from horizontal.
A matrix field is used during interpretation only. After that it is only a container field for the fields within it.
You cannot verify the matrix field in FORMS’ Verify module. It is only the fields within the matrix that are verified. Although the grid verifier combines individual fields visually, there is no single field value for a matrix.
The same goes for Transfer: The "value" of a matrix is never transfered. It is the values of the fields within the matrix that are transferred.
Specifying the position of columns in a matrix
Specifying the position of the data within each column of a matrix