In a unary operation in a mathematical system,one element is used to yield a single result. 在数学系统中的一元运算里,一个元素往往只产生一个单一的结果。
The requested metafile operation is not supported. 不支持请求的图元操作。
The context in which an operator symbol is used always determines whether the symbol represents a unary or binary operator. 对于这类操作符,需要根据该符号所处的上下文来确定它代表一元操作还是二元操作。