public NumberExpression<Double> sqrt() {
        if (sqrt == null) {
            sqrt = Expressions.numberOperation(Double.class, MathOps.SQRT, mixin);
        }
        return sqrt;
    }
Create a {@code sqrt(this)} expression

<p>Get the square root of this numeric expressions</p>

@return sqrt(this)
querydsl-core/src/main/java/com/querydsl/core/types/dsl/NumberExpression.java