Physicians routinely recommend a high-fiber diet that is full of roughage, or insoluble fiber, in order to keep things moving along. While this can be helpful, in some cases a high-fiber diet may actually promote intestinal infection. High-fiber diets are also high-residue diets.
The MATRIX program is designed to perform and to teach row operation algorithms on matrices. The program can work in a decimal floating-point mode in which calculations are carried out to 18 significant digits, or it can work in a fraction mode with exact rational arithmetic.
SAS/IML software has many useful built-in functions that generate matrices: You can create matrices as a result of a function call. Scalar functions such as LOG or SQRT operate on each element of a matrix, whereas matrix functions such as INV or RANK operate on the entire matrix. You can also create a row vector by using the index operator (:).