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Unformatted text preview: language rules have been violated, the computer
does not know that an error ha been made. Hence it will not produce any error
message for a logic error. Thus identifying logic errors in program is the
responsibility of the program development and testing team. The team tests the
program to determine whether or not it contains any logic error. The testing
procedure involves running the program to process input test data and comparing
the produced results with the known correct results. If the results generate for the
test data do not match with the known correct results, it is assumed that the
program contains one or mo: logic errors.
Logic errors are typically due either to missing logic or to incorrect logic. If the
logic is incorrect, the result generated from the test data will be wrong. These
errors are the easiest of the logic errors to find. Errors caused by missing logic
result from logical situations that the program was not designed to handle. As an
example suppose that a numeric field is to be used in an arithmetic process and
that the data entry operator enters a value for the field that is not numeric. The
program logic should determine that the data are not numeric prior attempting the
arithmetic process. If that logic is missing and nonnumeric data is used in an
arithmetic operation, the program will fail. This type of logic error can be difficult
to find. The only way for this error to occur is for nonnumeric data to be entered
into a numeric field. It is possible for the program to be used for weeks, months, or
years before this happens and the error in program logic shows up.
In order to completely test the program logic, the test data must test each logical
function of the program. Hence, the selection of proper test data is important in
program testing. In general, the test data selected for testing a program should
All types of possible valid data. This will test the generally used program
paths and will ensure that the program has been correctly designed to han...
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- Spring '14