SETSIG

Set signature for pseudo-Euclidean dataset or mapping

    B = SETSIG(A,SIG)
    B = A*SETSIG([],SIG);
    V = SETSIG(W,SIG);

Input
A	Dataset or data matrix (doubles)
SIG	Signature, 2-element vector with numbers of positive  and negative dimensions, default: all positive
W	Pseudo-Euclidean mapping created by PE_EM

Output
B	PE dataset
V	PE mapping

Description

Distances in a PE dataset are computed in a special way, see PE_DISTM using the signature of the PE space. This routine stores the signature  in the user-field of the dataset, so it can be used by any routine that  needs it. The signature is determined during a pseudo-Euclidean mapping,  e.g. by PSEM. Datasets applied to such a mapping obtain the signature  automatically. The signature is a vector of two elements equal to the  numbers of positive and negative eigenvalues found during the process of  PE mapping. Their sum should thereby be equal to the dimensionality of  the space, i.e. the number of features in A.

Note that V = W*SETSIG converts a pseudo-Euclidean mapping W into a  mapping V to the associated space.

See also

datasets, mappings, pe_em, pe_distm, getsig,