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Variable Random Options

Variable Random Options

The random options are only valid for variables which have an associated set of values. Only one of the two possible options may be used in a declaration; these option syntaxes are:

,RANDOM
,REPEATABLE {RANDOM} {,SEED = n}

These syntax elements are described below:

RANDOM

This option indicates that a value is to be selected randomly from a list or range, when the variable is used in conjunction with the GENERATE command. The values will be selected in a different order each time they are generated; this is achieved by generating a different seed value for the variable each time the variable is initialized. Local variables are initialized when Script execution begins. Script variables are initialized by the first thread to execute the Script.

This option is particularly useful when load testing a system.

This is the default if no random option is specified.

REPEATABLE {RANDOM}

This option indicates that a value is to be selected randomly from a list or range, when the variable is used in conjunction with the GENERATE command, but in the same order each time the Script is run. This is achieved by using the same seed value for the variable each time the variable is initialized.

This option is particularly useful in regression testing when reproducible input is required.

SEED = n

This option can be used in conjunction with the REPEATABLE RANDOM option, to specify the seed value that is to be used when generating the random sequence of numbers. This makes it possible to use a different sequence of random values for each repeatable random variable. n is a numeric literal in the range -2147483648 to +2147483647.


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