In the DIRA2 commands one can use query statements that return logical results. Correct statements are:

mag > 12. AND acod2(1:2) ='Sa'

COS(var1-var2) * SIN(var3).GT.(var4 + var5) /100.

NULL(radvel) .AND. (midiamb > 1.5 OR midiamr > 2.5 )

LOG(ABS( var1 - var2)) > 1. AND EMATCH( nota,"*STAR" )

Some DIRA2 commands allow one to evaluate new values from existing ones. With the DB_CALC command one can build a new column in a catalogue as numerical or logical function of the existing fields. Then one can use all the statements of the DIRA2 query language to define the catalogue new field. In other graphic commands as DB_REGRES or DB_SCHART, the values that one draws can be values of fields existing in the catalogue or values calculated as functions of existing fields. In these commands, the statement that one uses must define a numerical value.

1./SQRT(COS(alfa)**2 + SIN(beta)**2)

Where 'alfa' and 'beta' are catalogues fields.