www.gusucode.com > mbc 工具箱 matlab 源码程序 > mbc/@xregpointer/isnull.m
function null = isnull(p) %ISNULL Check whether pointer is null % % ISNULL(PTR) returns a logical array the same size as ptr which indicates % which pointers in ptr are null (do not point to a heap location). Note % that "null" is not the same concept as "valid", which checks whether the % heap location being pointed to is still in use or not. % Copyright 2000-2004 The MathWorks, Inc. and Ford Global Technologies, Inc. null = (p.ptr==0);