validation and verification

Validation is a method used to check that an input from a user is acceptable and matches the requirements of the program.

The six categories of validation are: range check, length check, type check, presence check, format check, and check digit.

A range check ensures the data entered as a number falls within a particular range.

A length check verifies that the length of a string meets specific criteria, such as a minimum or maximum number of characters.

A type check verifies that the data entered matches the expected data type, such as ensuring an age is entered as an integer.

A presence check looks to see if any data has been entered in a field, ensuring that required fields are not left blank.

A format check ensures that the data has been entered in the correct format, often using pattern matching and string handling.

Verification is the act of checking that data is accurate when entered into a system.

Two methods of verification are double entry checking and visual checks.

A check digit is a numerical value, usually the final digit of a larger code, calculated by applying an algorithm to the code to verify its accuracy.

Suitable test data is specially chosen data to test the functionality of a program or design.

The four categories of suitable test data are: normal, abnormal, extreme, and boundary.

Normal test data is data that should be accepted in the program.

Abnormal test data is data that is the wrong data type for the input field.

Extreme test data is the maximum and minimum values of normal data that are accepted by the system.

Boundary test data tests values on either side of the maximum and minimum acceptable values, including the largest and smallest unacceptable values.

False. Suitable test data is used to test both correct functionality and how the program handles incorrect inputs.

The purpose of using different categories of test data is to thoroughly test various aspects of the program, including its ability to handle both valid and invalid inputs.

Boundary test data would include ages: 18,25 -smallest & largest accepted data 17 & 26 - data falling just below & exceeding

It's important to test with abnormal data to ensure the program can handle incorrect input types and doesn't crash or behave unexpectedly when given invalid data.

A trace table is used to test algorithms and programs for logic errors that appear when an algorithm or program executes.

Program code.

Two purposes of using a trace table are: discover the purpose of an algorithm and record the state of the algorithm at each step or iteration.

A trace table is executed by following each stage of the algorithm step by step.

False. Trace tables can be used with flowcharts, pseudocode, or program code.

Inputs, outputs, variables, and processes can be checked for the correct value at each completed stage using a trace table.

In a trace table, each row typically represents a single step or iteration of the algorithm.

Trace tables are particularly useful for identifying logic errors that appear when an algorithm or program executes.