v point meaning in English

天底点

If the v points toward the left , the task is behind schedule
如果v指向左，表明任务比日程落后。
If the v points toward the right , the task is ahead of schedule
如果v指向右，表明任务比日程超前。
A directed balanced incomplete block design ( dbibd ) with order v , block size k and index a , denoted by db ( k , ? ; v ) , is a pair ( x , a ) , where x is a set of v points and a is a collection of transitively ordered k - tuples ( called blocks ) of x , such that each ordered pair of distinct points of x occurs exactly in a blocks
一个阶为v ，指标为及区组大小为k的有向平衡不完全区组设计， db ( k ，； v ) ，是指一个序偶( x ， a ) ，其中x是一个v元点集， a是x的一族可迁有序k元子集(叫做区组) ，使得x中任意两个相异点组成的有序对恰出现在个区组中。