Using the C Math Library

Assigning to a Subarray 

Use two vector indices to generate a matrix destination. For example, let the vector index B = [1 2], and the vector index C = [2 3]. Then,

mlfAssign(&source, mlfVertcat(mlfHorzcat(mlfScalar(1),
                                         mlfScalar(4),
                                         NULL),
                              mlfHorzcat(mlfScalar(3),
                                         mlfScalar(2),
                                         NULL),
                              NULL));
mlfIndexAssign(&A, "(?,?)", B, C, source);

copies a 2-by-2 matrix into the second and third columns of rows 1 and 2: the upper right corner of A. The example matrix A becomes:

1 1 4
2 3 2
3 6 9

You can also use a logical matrix as an index. For example, let B be the logical matrix:

0 1 1
0 1 1
0 0 0

Then,

mlfIndexAssign(&A, "(?)", B, source);

changes A to:

1 1 4
2 3 2
3 6 9

Assigning to Multiple Elements

Assigning to All Elements