spScale

Purpose

Scales a sparse matrix.

Format

{ a, r, s } = spScale(x)
Parameters:

x (MxN sparse matrix) – data

Returns:
  • a (MxN sparse matrix) – scaled sparse matrix.
  • r (Mx1 vector) – row scale factors.
  • s (Nx1 vector) – column scale factors.

Examples

x = { 25  -12    0,
       3    0  -11,
       8 -100    0 };

declare sparse matrix sm, smsc;
sm = denseToSp(x, 0);

{ smsc, r, c } = spScale(sm);

The results:

        2.50  -0.12   0.00
smsc =  0.30   0.00  -0.11
        0.80  -1.00   0.00

        1.00
c =     0.10
        0.10

        0.10
r =     0.10
        0.10

Remarks

spScale() scales the elements of the matrix by powers of 10 so that they are all within \((-10,10)\).