Defining a Matrix

The fundamental data object on which all Interactive Matrix Language commands operate is a two-dimensional (row column) numeric or character matrix. By their very nature, matrices are useful for representing data and efficient for working with data. Matrices have the following properties:

• Matrices can be either numeric or character. Elements of a numeric matrix are stored in double precision. Elements of a character matrix are character strings of equal length. The length can range from 1 to 32676 characters.
• Matrices are referred to by valid SAS names. Names can be from 1 to 32 characters long, beginning with a letter or underscore, and continuing with letters, numbers, and underscores.
• Matrices have dimension defined by the number of rows and columns.
• Matrices can contain elements that have missing values (see the section "Missing Values").

The dimension of a matrix is defined by the number of rows and columns it has. An matrix has elements arranged in rows and columns. The following nomenclature is standard in this user's guide:

• matrices are called row vectors.
• matrices are called column vectors.
• matrices are called scalars.

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