public NumberExpression<Double> doubleValue() {
        return castToNum(Double.class);
    }
Create a {@code cast(this as double)} expression

<p>Get the double expression of this numeric expression</p>

@return this.doubleValue()
@see java.lang.Number#doubleValue()
querydsl-core/src/main/java/com/querydsl/core/types/dsl/NumberExpression.java