ARITH

 

  +   Plus.

       X + Y adds matrices X and Y.  X and Y must have the same

       dimensions unless one is a scalar (a 1-by-1 matrix).

       A scalar can be added to anything.  

 

 

   -   Minus.

       X - Y subtracts matrix X from Y.  X and Y must have the same

       dimensions unless one is a scalar.  A scalar can be subtracted

       from anything.  

 

 

   *   Matrix multiplication.

       X*Y is the matrix product of X and Y.  Any scalar (a 1-by-1 matrix)

       may multiply anything.  Otherwise, the number of columns of X must

       equal the number of rows of Y.

 

 

   .*  Array multiplication

       X.*Y denotes element-by-element multiplication.  X and Y

       must have the same dimensions unless one is a scalar.

       A scalar can be multiplied into anything.

 

 

   ^   Matrix power.

       Z = X^y is X to the y power if y is a scalar and X is square. If y is an

       integer greater than one, the power is computed by repeated

       multiplication. For other values of y the calculation

       involves eigenvalues and eigenvectors.

       Z = x^Y is x to the Y power, if Y is a square matrix and x is a scalar,

       computed using eigenvalues and eigenvectors.

       Z = X^Y, where both X and Y are matrices, is an error.

 

 

   .^  Array power.

       Z = X.^Y denotes element-by-element powers.  X and Y

       must have the same dimensions unless one is a scalar. 

       A scalar can operate into anything.

  Copyright (c) 1984-93 by The MathWorks, Inc.