Dense => default value false, whether the encoding of the matrix should be dense or not: see MutableMatrix
Outputs:
a mutable matrix, a random mutable nrows by ncols matrix of integers. The absolute value of the entries is less than max, and the frequency of entries equal to zero is given by zerof.
Description
This function has been superceded by fillMatrix, which works over more rings, is much faster for large matrices, and is more flexible.