[classad-users] Ranks and Requirements

[Kaizar Amin <amin@xxxxxxxxxxx>]

Hi,

As per my understanding, the match function in ClassAd.java
"public static int[] match(Expr expr1, Expr expr2)"
seems to work on the following principles:
1. There MUST exist a REQUIREMENT and RANK attribute in both classads
 - What happens when there is no requirement attribute, does it default 
to true or does the match fail
 - What happens when there is no RANK attribute

2. So far, my assumption is that Requirement attribute is some 
combination of Boolean expressions and Rank is some integer value.
 - However, in the condor manual I saw the following example:

    Friend        = Owner == "tannenba" || Owner == "wright"
    ResearchGroup = Owner == "jbasney" || Owner == "raman"
    Trusted       = Owner != "rival" && Owner != "riffraff"
    Requirements  = Trusted && ( ResearchGroup || LoadAvg < 0.3 &&
                         KeyboardIdle > 15*60 )
    Rank          = Friend + ResearchGroup*10
In this case "Friend" is a boolean attribute, how is it evaluated into 
an integer value.

Thanks for your help.
Kaizar
Condor Classads Info:
http://www.cs.wisc.edu/condor/classad/