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| {{Refimprove|date=August 2008}}
| | <br><br>In at the moment's quick-paced world, do most people discover 24 hours a day sufficient to accomplish the tasks that they wanted to? As a rule, they may discover that they do not have sufficient time. This lack of time, load and pressure of work creates nervousness and produces panic conditions. The result is mind filled with tensions and worries. All these elements mixed trigger lack of sleep, loss of well being and other kinds of mental and bodily sicknesses.<br><br>For those who suppose you'll have an anxiety dysfunction, talk to your major care doctor about your symptoms and ask for a referral to a medical professional who can diagnose and treat anxiousness. There are numerous good sources of details about anxiousness and different varieties of mental sickness on the Internet, by way of libraries and from mental health organizations. Many organizations have hotlines to assist get you started speaking about signs. For those who really feel suicidal, search assist instantly.<br><br>Anti depressants have been used for treating anxietydisorders, and take a longer time to see the effects, starting from four to 6weeks. They're often prescribed rather than anti anxiety medicine as there isless danger of addiction, but they have severe unwanted effects including suicidalthoughts and agitation. They may also improve melancholy. Tricyclics and Monoamine oxidase inhibitors (MAOIs) areolder courses of antidepressants. Tricyclics will be mixed with SSRIs foranxiety problems aside from OCD. Nevertheless, MAOIs should not be taken with SSRIsas they react to produce hallucinations, seizures and blood stress changes. Alcohol Research and Well being. Sarah W. Guide, Carrie L. Randall. Social anxiousness dysfunction and alcohol use Retrieved February 24, 2006.<br><br>This would possibly seem like dangerous news in case you are a panic assault sufferer however fortunately you possibly can management it just by studying learn how to breathe correctly in these conditions. Sounds simple but it surely's not. Why? As a result of when you're breathing an excessive amount of oxygen, your brain is aware of it and compensates, however, the sensation it causes is the complete opposite, making you actually do the other of what it is best to, i.e., breath in more oxygen when you have to be retaining more carbon dioxide. Fairly onerous when it makes you're feeling like you're suffocating!<br><br>It must be famous that the latter forms of anxiety disorder are mirrored in a different way depending on a number of demographic traits. As an illustration, age is a crucial issue as a result of youngsters's forms of anxiety problems are manifested in unique varieties; some of them may be afraid of monsters in the closet or eyes watching them at evening. Kids may additionally specific these anxieties in completely different manners from their grownup counterparts. Gender is one other important demographic trait. Women are more involved with sure obsessions or ideas in comparison to their male counterparts. Also, cultural influenced have a big part to play. |
| {{portal|Software Testing}}
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| '''Equivalence partitioning''' (also called '''Equivalence Class Partitioning''' or '''ECP'''<ref>{{Citation
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| |title=Practical Software Testing
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| |first1=Ilene
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| |last1=Burnstein
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| |publisher=Springer-Verlag
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| |year=2003
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| |isbn=0-387-95131-8
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| |page=623
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| }}</ref>) is a [[software testing]] technique that divides the input data of a software unit into partitions of equivalent data from which test cases can be derived. In principle, test cases are designed to cover each partition at least once. This technique tries to define test cases that uncover classes of errors, thereby reducing the total number of test cases that must be developed. An advantage of this approach is reduction in the time required for testing a software due to lesser number of test cases.
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| Equivalence partitioning is typically applied to the inputs of a tested component, but may be applied to the outputs in rare cases. The equivalence partitions are usually derived from the requirements specification for input attributes that influence the processing of the test object.
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| The fundamental concept of ECP comes from [[equivalence class]] which in turn comes from [[equivalence relation]]. | |
| A software system is in effect a [[computable function]] implemented as an [[algorithm]] in some implementation [[programming language]].
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| Given an input [[test vector]] some instructions of that algorithm get covered, ( see [[code coverage]] for details ) others do not.
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| This gives the interesting relationship between input test vectors:-
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| <math>_aC_b</math> is an [[equivalence relation]] between test vectors <math>a,b</math> if and only if the coverage foot print of the | |
| vectors <math>a,b</math> are exactly the same, that is, they cover the same instructions, at same step.
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| This would evidently mean that the relation cover <math>C</math> would partition the input [[vector space]] of the [[test vector]]
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| into multiple [[equivalence class]]. This partitioning is called equivalence class partitioning of test input.
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| If there are <math>N</math> equivalent classes, only <math>N</math> vectors are sufficient to fully cover the system.
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| The demonstration can be done using a function written in [[C (programming language)|C]]:
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| <source lang="c">
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| int safe_add( int a, int b )
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| {
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| int c = a + b;
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| if ( a >= 0 && b >= 0 && c < 0 )
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| {
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| fprintf ( stderr, "Overflow!\n" );
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| }
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| if ( a < 0 && b < 0 && c >= 0 )
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| {
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| fprintf ( stderr, "Underflow!\n" );
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| }
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| return c;
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| }
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| </source>
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| On the basis of the code, the input vectors of <math>[a,b]</math> are partitioned. The blocks we need to cover are the overflow statement and the underflow statement and neither of these 2. That gives rise to 3 equivalent classes, from the code review itself.
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| [[File:ECP.png|thumb||right| Demonstrating Equivalence Class Partitioning]]
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| To solve the input problem, we take refuge in the [[inequation]]
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| <math>
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| z_{min} \le x + y \le z_{max}
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| </math>
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| we note that there is a fixed size of [[Integer (computer science)]] hence, the z can be replaced with:-
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| <math>
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| INT\_MIN \le x + y \le INT\_MAX
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| </math>
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| and | |
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| with <math>x \in \{ INT\_MIN , ... , INT\_MAX \}</math> and <math>y \in \{ INT\_MIN , ... , INT\_MAX \}</math>
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| The values of the [[test vector]] at the strict condition of the equality that is <math> INT\_MIN = x + y </math> and <math> INT\_MAX = x + y </math> are called the boundary values, [[Boundary-value analysis]] has detailed information about it. Note that the graph only covers the overflow case, first quadrant for X and Y positive values.
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| In general an input has certain ranges which are valid and other ranges which are invalid. Invalid data here does not mean that the data is incorrect, it means that this data lies outside of specific partition. This may be best explained by the example of a function which takes a parameter "month". The valid range for the month is 1 to 12, representing January to December. This valid range is called a partition. In this example there are two further partitions of invalid ranges. The first invalid partition would be <= 0 and the second invalid partition would be >= 13.
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| ... -2 -1 0 1 .............. 12 13 14 15 .....
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| --------------|-------------------|---------------------
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| invalid partition 1 valid partition invalid partition 2
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| The testing theory related to equivalence partitioning says that only one test case of each partition is needed to evaluate the behaviour of the program for the related partition. In other words it is sufficient to select one test case out of each partition to check the behaviour of the program. To use more or even all test cases of a partition will not find new faults in the program. The values within one partition are considered to be "equivalent". Thus the number of test cases can be reduced considerably.
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| An additional effect of applying this technique is that you also find the so-called "dirty" test cases. An inexperienced tester may be tempted to use as test cases the input data 1 to 12 for the month and forget to select some out of the invalid partitions. This would lead to a huge number of unnecessary
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| test cases on the one hand, and a lack of test cases for the dirty ranges on the other hand.
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| The tendency is to relate equivalence partitioning to so called [[black box testing]] which is strictly checking a software component at its interface, without consideration of internal structures of the software. But having a closer look at the subject there are cases where it applies to [[grey box testing]] as well. Imagine an interface to a component which has a valid range between 1 and 12 like the example above. However internally the function may have a differentiation of values between 1 and 6 and the values between 7 and 12. Depending upon the input value the software internally will run through different paths to perform slightly different actions. Regarding the input and output interfaces to the component this difference will not be noticed, however in your grey-box testing you would like to make sure that both paths are examined. To achieve this it is necessary to introduce additional equivalence partitions which would not be needed for black-box testing. For this example this would be:
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| ... -2 -1 0 1 ..... 6 7 ..... 12 13 14 15 .....
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| --------------|---------|----------|---------------------
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| invalid partition 1 P1 P2 invalid partition 2
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| valid partitions
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| To check for the expected results you would need to evaluate some internal intermediate values rather than the output interface. It is not necessary that we should use multiple values from each partition. In the above scenario we can take -2 from invalid partition 1, 6 from valid partition P1, 7 from valid partition P2 and 15 from invalid partition 2.
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| Equivalence partitioning is not a stand alone method to determine test cases. It has to be supplemented by [[boundary value analysis]]. Having determined the partitions of possible inputs the method of boundary value analysis has to be applied to select the most effective test cases out of these partitions.
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| ==Further reading==
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| * [http://www.testingstandards.co.uk The Testing Standards Working Party website]
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| * [http://parteg.sourceforge.net Parteg], a free test generation tool that is combining test path generation from UML state machines with equivalence class generation of input values.
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| * [http://books.google.co.in/books/about/Software_Testing_Techniques.html]
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| == References ==
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| {{Reflist}}
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| | |
| [[Category:Software testing]]
| |
In at the moment's quick-paced world, do most people discover 24 hours a day sufficient to accomplish the tasks that they wanted to? As a rule, they may discover that they do not have sufficient time. This lack of time, load and pressure of work creates nervousness and produces panic conditions. The result is mind filled with tensions and worries. All these elements mixed trigger lack of sleep, loss of well being and other kinds of mental and bodily sicknesses.
For those who suppose you'll have an anxiety dysfunction, talk to your major care doctor about your symptoms and ask for a referral to a medical professional who can diagnose and treat anxiousness. There are numerous good sources of details about anxiousness and different varieties of mental sickness on the Internet, by way of libraries and from mental health organizations. Many organizations have hotlines to assist get you started speaking about signs. For those who really feel suicidal, search assist instantly.
Anti depressants have been used for treating anxietydisorders, and take a longer time to see the effects, starting from four to 6weeks. They're often prescribed rather than anti anxiety medicine as there isless danger of addiction, but they have severe unwanted effects including suicidalthoughts and agitation. They may also improve melancholy. Tricyclics and Monoamine oxidase inhibitors (MAOIs) areolder courses of antidepressants. Tricyclics will be mixed with SSRIs foranxiety problems aside from OCD. Nevertheless, MAOIs should not be taken with SSRIsas they react to produce hallucinations, seizures and blood stress changes. Alcohol Research and Well being. Sarah W. Guide, Carrie L. Randall. Social anxiousness dysfunction and alcohol use Retrieved February 24, 2006.
This would possibly seem like dangerous news in case you are a panic assault sufferer however fortunately you possibly can management it just by studying learn how to breathe correctly in these conditions. Sounds simple but it surely's not. Why? As a result of when you're breathing an excessive amount of oxygen, your brain is aware of it and compensates, however, the sensation it causes is the complete opposite, making you actually do the other of what it is best to, i.e., breath in more oxygen when you have to be retaining more carbon dioxide. Fairly onerous when it makes you're feeling like you're suffocating!
It must be famous that the latter forms of anxiety disorder are mirrored in a different way depending on a number of demographic traits. As an illustration, age is a crucial issue as a result of youngsters's forms of anxiety problems are manifested in unique varieties; some of them may be afraid of monsters in the closet or eyes watching them at evening. Kids may additionally specific these anxieties in completely different manners from their grownup counterparts. Gender is one other important demographic trait. Women are more involved with sure obsessions or ideas in comparison to their male counterparts. Also, cultural influenced have a big part to play.