Package org.cqframework.cql.elm.execution

Class Less

  • All Implemented Interfaces:
    org.jvnet.jaxb2_commons.lang.Equals2, org.jvnet.jaxb2_commons.lang.HashCode2, org.jvnet.jaxb2_commons.lang.ToString2
    Direct Known Subclasses:
    LessEvaluator
    public class Less
extends BinaryExpression
implements org.jvnet.jaxb2_commons.lang.Equals2, org.jvnet.jaxb2_commons.lang.HashCode2, org.jvnet.jaxb2_commons.lang.ToString2
    The Less operator returns true if the first argument is less than the second argument. For comparisons involving quantities, the dimensions of each quantity must be the same, but not necessarily the unit. For example, units of 'cm' and 'm' are comparable, but units of 'cm2' and 'cm' are not. Attempting to operate on quantities with invalid units will result in a null. When a quantity has no units specified, it is treated as a quantity with the default unit ('1'). For time-valued quantities, the UCUM definite-quantity durations above days (and weeks) are not comparable to calendar durations. Definite-time duration unit conversions shall be performed as specified in ISO-8601, while calendar-time duration unit conversions shall be performed according to calendar duration semantics. In particular, unit conversion between variable length calendar durations (i.e. years and months) and definite-time durations (i.e. days or below) results in null. For Date, Time, and DateTime values, the comparison is performed by considering each precision in order, beginning with years (or hours for time values). If the values are the same, comparison proceeds to the next precision; if the first value is less than the second, the result is true; if the first value is greater than the second, the result is false; if one input has a value for the precision and the other does not, the comparison stops and the result is null; if neither input has a value for the precision or the last precision has been reached, the comparison stops and the result is false. For the purposes of comparison, seconds and milliseconds are combined as a single precision using a decimal, with decimal comparison semantics. If either argument is null, the result is null. The Less operator is defined for the Integer, Long, Decimal, String, Date, DateTime, Time, and Quantity types. Note that relative ratio comparisons are not directly supported due to the variance of uses within healthcare. See the discussion in Ratio Operators in the Author's Guide for more information.

    Java class for Less complex type.

    The following schema fragment specifies the expected content contained within this class. 

     <complexType name="Less">
   <complexContent>
     <extension base="{urn:hl7-org:elm:r1}BinaryExpression">
     </extension>
   </complexContent>
 </complexType>