star (*) multiplication operator

## Description

Multiplication. Usual meaning. Valid for constant, boolean, polynomial, rational matrices and for `syslin` lists (the meaning is series connection).

Element-wise multiplication is denoted `x.*y`. If `x` or `y` is scalar (1x1 matrix) `.*` is the same as `*`.

Kronecker product is `x.*.y`.

`A*.B` is an operator with no predefined meaning. It may be used to define a new operator (see overloading) with the same precedence as `*` or `/`.

Remark that `/*` start to comment a block of code and `*/` end to comment this block.

## Examples

    // Basic numerical operations
    2 * 2 // 4
    2 * [%pi, %eps] // 6.2831853    4.441D-16
    rand(2,2) * rand(2)
    [1, 2; 3, 4] * [%pi,%eps; %e, %pi]

    // Polynomial operations
    s=poly(0,"s");
    p=1+s+2*s^2;
    q=1+s+2*s^3;
    p * q
    //               2    3    4    5
    //    1 + 2s + 3s + 4s + 2s + 4s

    // Rational
    s=poly(0,'s');
    W=[1/s,1/(s+1)];
    W' * W
    //    1           1
    //    -         -----
    //     2             2
    //    s         s + s
    //
    //      1           1
    //    -----     ---------
    //         2              2
    //    s + s     1 + 2s + s

## See also

- dot
- slash
- backslash
- syslin
- overloading
- comments