Numerical Operands

If both A and B are matrices, then A \ B is the (numerical) solution of matrix equation A X = B. The matrix A must be an non-singular square matrix and B must have n rows. For example
>>  A = [1, 2, -3; 2, 1, 5; 0, -1, 5];
>>  b = [3; 1; -2];
>>  x = A \ b
     0.75 
     0.75
    -0.25 

>>  A * x
    3        
    1 
   -2
>> norm(A*x-b)
    2.220446049e-16
Note that is only approximately equal to .

oz 2009-12-22