ngspice又一个电子CAD仿真软件代码.功能更全

				/* $Id: pnode.h,v 1.2 2005/05/26 19:30:53 sjborley Exp $ */				#ifndef _PNODE_H				#define _PNODE_H								struct pnode {				    char *pn_name;		/* If non-NULL, the name. */				    struct dvec *pn_value;	/* Non-NULL in a terminal node. */				    struct func *pn_func;	/* Non-NULL is a function. */				    struct op *pn_op;		/* Operation if the above two NULL. */				    struct pnode *pn_left;	/* Left branch or function argument. */				    struct pnode *pn_right;	/* Right branch. */				    struct pnode *pn_next;	/* For expression lists. */				    int pn_use;			/* usage counter */				} ;								#endif