lowest value of - Pacific Knowledge Systems

lowest value of finds the maximum value within a set of attribute values. The simplest syntax is

lowest value of { names } in range [lower, upper]

where:

names are comma separated lists of attribute names or group attribute names

lower and upper are numeric constants.

Another possible syntax is

lowest value of calculation

where:

calculation is a calculated value attribute defining a set of attributes using the in range function.

A typical use of this function is to compare the lowest value from two sets of attribute values. For example, suppose we have a calculated value attribute HighFood defined as:

{milk, cod, peanut} in range [15.0, 50)

and a calculated value attribute HighPollen defined as:

{birch, timothy} in range [15.0, 50)

and a case as follows:

age            6
sex            F
milk           0.0
peanut         43.5
cod            32.1
birch          24.6
timothy        25.3
HighFood       peanut (43.5) and cod (32.1)
HighPollen     timothy (25.3) and birch (24.6)

Then the following conditions are all true for this case:

lowest value of HighFood is 32.1

lowest value of HighPollen is 24.6

lowest value of HighFood > lowest value of HighPollen

Another typical use is in finding the lowest value in a case of the attributes in a group. For example, suppose that we have

HighGroups = (HighAllergens as groups from {food, pollen}) not in ((ModerateGroups union LowGroups) union VeryLowGroups)

then

lowest value of HighGroups

will evaluate for a case as follows. First, HighGroups is evaluated, to give a set of group attributes. For each of these group attributes, the lowest value in the case of the attributes in the group is found. The lowest of these ‘group minimum’ values is returned.