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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 /.

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 — (.) symbol
• slash — (/) right division and feed back
• backslash — (\) left matrix division.
• syslin — linear system definition
• overloading — display, functions and operators overloading capabilities