if and only if/iff是什么意思

网络释义

用法例句

An edge is a bridge if it is not contained in a cycle.

一条边是桥当且仅当它不包含在圈中。

Two sets are said to be equivalent if and only if they can be placed in one-to-one correspondence.

当且仅当两个集合中的元素一一对应时，才称它们为等势。

Positive semi-definite matrices are positive definite if and only if they are nonsingular.

正半定矩阵是正定的，当且仅当它们是非奇异矩阵。

Axiom1: If a property is positive, then its negation is not positive.

公理1:一个性质是肯定的当且仅当它的否定是否定的.

A node-set is true if and only if it is non-empty.

一个节点当且仅当它不是空节点时，表达式的值为真。

The Boolean operation whose result has the Boolean value 0 if and only if each operand has the Boolean value 0.

一种布尔运算,当且仅当每个操作数都具有布尔值0时,其结果才具有布尔值0。

a threshold operation in which each operand is 0 or 1; output is 1 if and only if more than half the operands have the value 1.

每个操作数只能取或的一种阈值操作；当且仅当超过一半的操作数取值为时结果值为。

There's another logic operation called exclusive OR, in which the compound sentence is false, not true, if and only if all the components are true.

还有另外一种逻辑操作叫做异或：当且仅当所有的成员为真时,结果才为假。”

It's not only hot today, but the smog is quite bad.

今天不仅是天气热，而且烟雾相当糟。

The economic value has jumped ten times not only for this piece of land, but also for the neighborhood.

经济价值涨了10倍，不仅仅是当地的地价，而且连周边的城市也涨了。

I thought, working as an editor, I must learn Chinese well in addition to having a good command of English.

我当时认为，当编辑不仅要精通英语，而且还要学好汉语。

Luis is a killer. She not only spikes hard but also has tremendous spring.

路易斯是个球场杀手，她不仅重扣有力，而且弹跳力相当好。

Although the ultraviolet ray only occupies the sunlight3%, also the suitable ultraviolet radiation has the sterilization.

紫外线虽然仅占阳光的3%且适当的紫外线辐射具有杀菌作用。

Miss Wang was not only their interpreter, but she acted as guide during the whole trip.

在整个旅游过程中，王小姐不仅是他们的翻译而且还担当向导

A falsely glowing report is not only pointless, it can be dangerous.

一份漂亮但不真实的评估报告不仅毫无意义，而且可能相当危险。

As n increases, the vertical lines not only become more numerous but also tend to bunch up together to form a bell shape.

当n增加时，不仅垂线愈来愈近，而且趋向于钟形曲形。

As we change and adapt, we not only survive, but we grow and evolve.

当我们改变和适应生活时，我们不仅生存，并且成长和进化。

PinYin Input Edit Method is easy to grasp, and has a great many customers in market.

拼音输入法不仅具有易学易会的特点,而且拥有相当多的用户。