组合测试（CombinatorialTest）配对测试（pairwi）
成对测试（Pairwi Testing）⼜称结对测试、两两测试，是⼀种正交分析的测试技术。
成对组合覆盖这⼀概念是Mandl于1985年在测试Aad编译程序时提出来的。是当不可能遍历产品所有功能点时⽤到的⼀种测试⼿段，即如
果⽤尽可能少的⼯作发现最多的缺陷（测试投⼊产出性价⽐）。
经验证，Cohen等⼈应⽤成对组合覆盖测试技术对Unix中的“Sort”命令进⾏了测试。测试结果表明覆盖率⾼达90%以上，可见成对成对测试是⼀种⾮常有效的测试⽤例设计⽅法。
facebook是什么
成对组合覆盖要求任意两个因素（输⼊条件）的所有⽔平组合⾄少要被覆盖1次。实现成对组合覆盖的算法⼯具有很多，其中微软的PICT就是其中⼀个。
测试⽤例⽣成⼯具 —— PICT(Pairwi Independent Combinatorial Testing tool)
PICT 可以有效地按照两两测试的原理，进⾏测试⽤例设计.在使⽤PICT时，需要输⼊与测试⽤例相关的所有参数，以达到全⾯覆盖的效果。
Pairwi Testing
t-wi testing is t-wi testing with a thoroughness of t.
The term all-pairs testing is simply equivalent to pairwi testing.
noveltyMixed-strength testing is to mix, for example, 2-wi and 3-wi testing in the same round of testing.
Combinatorial testing is a more general term that includes pairwi testing but also other testing techniques.
Combinatorial testing > Pairwi testing > Orthogonal array testing
Pairwi testing fits nicely into the testing pha of software or hardware development. It works well with agile development practices. Pairwi testing is usually not fully automatic. Pairwi testing usually requires some manual work to describe the thing that is to be tested. Usually a pairwi testing tool then takes this description (or model) and generates the pairwi tests automatically.
Pairwi testing is more focud on putting your system into varied situations.
Having a domain expert make tests for a software or hardware system is valuable and highly recommended.
Pairwi testing is not a replacement for this kind of testing but complementary to it.
Pairwi tests acts in a similar way, it explores the different paths of interaction.
From a ur’s point of view, pairwi testing is light-weight and simple to apply to even the larger cas.
foolproofFrom the pairwi tool developer’s point of view, however, pairwi testing involves some heavy-weight computations. This was until the last few years a bottleneck in the application of pairwi testing to the larger real-life cas, but in recent years effective algorithms for pairwi testing has been invented and are now available in commercial products.>>> Some on the computations.
自考英语写作
sackingThe effectiveness of pairwi testing is neither hypothetical nor only academic. The effectiveness of pairwi testing has been studied by looking at existing large-scale software or hardware and their histories of problems and bugs. As the thoroughness of pairwi testing increas, it has been found that increasing amounts of bugs can be found. I one large study, it was found that for a thoroughness of 1, 2 and 3, the percentage of bugs that might be found was 50, 75 and 90%, respectively. This study found no bugs that required more than a thoroughness of 6, a result that has stood the test of time. This is the reason why a thoroughness of 6 is usually the maximum considere
d. As the thoroughness of pairwi testing increas, so does the effort required to do the tests. A thoroughness of 2, i.e. 2-wi or pairwi, has a very good tradeoff between thoroughness and effort. A thoroughness of 3 is a good for more important rounds of testing, for example, for later stages of development.
For testing highly critical software of hardware, pairwi testing is a good start, but other quality assurance techniques should be ud in addition.
Partial thoroughness
A pairwi test suite might contain, for example, 30 test cas. The accumulated coverage after each test ca has been added will typically form a curve like this:
英文人名
图表作文As we can e in this example, the first 12 tests include more than 95% of the pairs. So, the last 18 tests cover less than 5%.
In ordinary pairwi test generation, the pairs included (pudo-)randomly, meaning that any faulty pair is most likely to be included early in the test suite. Thus, a partial test suite of, for example, 95% can be expected to detect 95% of the bugs that a complete pairwi test suite would find.
环保材料 英语>opera什么意思(Web-bad, free & commercial)
Pairwi testing is not well suited for a testing problem with a few parameters with relatively many combinations. As we will e in other examples, pairwi testing performs very well when we have more parameters, which the most interesting, real industrial cas surely tend to have!
开除英文Pairwi testing was combined with a kind of equivelence class lection technique to reduce the number of values to include for generating the pairwi tests. This is a quite common technique to combine with pairwi testing.
Total inputs:
The parameters: primary/cond/...
The constrains: always hen..
The required test cas.
(Web-bad, free)
>>> Paper:
