SDNOMINAL Test and define nominal data representation

 Display nominal feature information
    SDNOMINAL(A)
    SDNOMINAL(P)

 Test if numerical representation of nominal data is identical
    I=SDNOMINAL(A,B)  or I=SDNOMINAL(A,P)

 Update data matrix of A with nominal representation in B
    A2=SDNOMINAL(A,'from',B)       % A2 and B are comparable

 Join nominal representations in A and B and update both
    [A3,B3]=SDNOMINAL(A,'join',B)  % A3 and B3 are comparable

 Remove nominal information from data set or pipeline
    A4=SDNOMINAL(A,'remove')

 INPUTS
    A,B          sddata sets
    P            trained pipeline

 OUTPUTS
    I            indicator 1 if both sets are comparable, 0 if not
    A2           sddata set A with nominal rep. compatible with B
    A3,B3        sddata sets A and B with joined nom.rep. (classifier
                 trained on A3 may be used on B3)
    A4           data set without nominal information

 OPTIONS
   'nodisplay'   Do not show comments
   'from',B      pass nominal rep. from B to A (update data matrix)
   'join',B      join nominal rep. in A and B (update both data matrices).
   'remove',A    remove nominal rep.meta-data from A (unchanged data matrix)

 DESCRIPTION
 When nominal features are present in the data set, their numerical
 representation is defined by featlist sdlist of nominal categories.  To
 use the same classifier, data sets must share the same nominal
 representation.

 SDNOMINAL command allows one to check if two data sets share the same
 numerical representation of nominal data, update representation based on
 other set or join two nominal representations and update both sets.

 EXAMPLE
 I=sdnominal(A,B); % if I==0, classifier trained on A cannot be used on B

 SEE ALSO
 ISNOMINAL

sdnominal is referenced in examples:

• kb28: Example on building a classifier on database records