rand (Function)
This returns a stream of pseudo-random numbers when a sequence of calls are sent to the rand(). Optionally, it is possible to define a seed, i.e., rand(seed) using which the pseudo-random numbers are generated. These functions internally use the java.util.Random class.
Syntax
<DOUBLE> math:rand()
<DOUBLE> math:rand(<INT|LONG> seed)
Query Parameters
| Name | Description | Default Value | Possible Data Types | Optional | Dynamic |
|---|---|---|---|---|---|
| seed | An optional seed value that will be used to generate the random number sequence. | defaultSeed | INT LONG | Yes | Yes |
Example 1
CREATE STREAM InValueStream (symbol string, price long, volume long);
@info(name = 'generateRandomNumber')
INSERT INTO OutMediationStream
SELECT symbol, math:rand() AS randNumber
FROM InValueStream;
The generateRandomNumber query processes the input stream InValueStream, which contains three fields: symbol, price, and volume. For each event in the input stream, the query generates a random double value between 0 (inclusive) and 1 (exclusive) using the math:rand() function.
The random number is aliased as randNumber, and the output stream OutMediationStream contains the symbol and the generated randNumber. This query processes the input stream events and forwards the resulting random numbers along with the symbol to the output stream for further processing or analysis.