public static <A extends Number & Comparable<?>> NumberExpression<Integer> sign(Expression<A> num) {
        return Expressions.numberOperation(Integer.class, Ops.MathOps.SIGN, num);
    }
Create a {@code sign(num)} expression

<p>Returns the positive (+1), zero (0), or negative (-1) sign of num.</p>

@param num numeric expression
@return sign(num)
querydsl-core/src/main/java/com/querydsl/core/types/dsl/MathExpressions.java