@Override
    protected Object[] process(Object[] data) {

        double theta = (Double) data[0];
        double rho = (Double) data[1];
        Object[] output = new Object[inputExecutorLength];
        output[0] = rho * Math.cos(Math.toRadians(theta));
        output[1] = rho * Math.sin(Math.toRadians(theta));
        if (inputExecutorLength == 3) {
            output[2] = data[2];
        }
        return output;
    }
The process method of the StreamFunction, used when multiple function parameters are provided

@param data the data values for the function parameters
@return the date for additional output attributes introduced by the function
modules/siddhi-core/src/main/java/io/siddhi/core/query/processor/stream/function/Pol2CartStreamFunctionProcessor.java