function old = setGlobalStream(stream)

%RANDSTREAM.SETGLOBALSTREAM Replace the global random number stream.

%   PREVSTREAM = RandStream.SETGLOBALSTREAM(STREAM) sets STREAM as the current

%   global random number stream, i.e., designates it as the stream that the

%   RAND, RANDI, and RANDN functions will draw values from. PREVSTREAM is the

%   stream that was previously designated as the global random number stream.

%

%   RAND, RANDI, and RANDN all rely on the same stream of uniform pseudorandom

%   numbers, known as the global random number stream.  RAND draws one value

%   from that stream to generate each uniform value it returns;  RANDI draws

%   one uniform value from that stream to generate each integer value it

%   return; and RANDN draws one or more uniform values to generate each normal

%   value it returns.  Note that there are also RAND, RANDI, and RANDN methods

%   for which you specify a specific random stream from which to draw values.

%

%   The RNG function is a shorter alternative for many uses of

%   RANDSTREAM.setGlobalStream.

%

%   See also RNG, RANDSTREAM, RANDSTREAM.GETGLOBALSTREAM,

%            RANDFUN/RAND, RANDFUN/RANDN, RANDFUN/RANDI.

            if nargout > 0 

                old = localGetSetGlobalStream();

            end 

            localGetSetGlobalStream(stream); 

        end