www.gusucode.com > elmat工具箱matlab源码程序 > elmat/private/rando.m
function A = rando(n, k, classname) %RANDO Random matrix with elements -1, 0 or 1. % A = GALLERY('RANDO',N,K) is a random N-by-N matrix with % elements from one of the following discrete distributions % (default K = 1): % K = 1: A(i,j) = 0 or 1 with equal probability, % K = 2: A(i,j) = -1 or 1 with equal probability, % K = 3: A(i,j) = -1, 0 or 1 with equal probability. % N may be a 2-vector, in which case the matrix is N(1)-by-N(2). % Copyright 1984-2005 The MathWorks, Inc. if isempty(k), k = 1; end m = n(1); % Parameter n specifies dimension: m-by-n. n = n(length(n)); if k == 1 % {0, 1} A = floor( rand(m,n) + .5 ); elseif k == 2 % {-1, 1} A = 2*floor( rand(m,n) + .5 ) - 1; elseif k == 3 % {-1, 0, 1} A = round( 3*rand(m,n) - 1.5 ); end A = cast(A,classname);