unique

extract unique components of a vector or matrices

Calling Sequence

[N [,k]]=unique(M)
[N [,k]]=unique(M ,orient)

Arguments

:M vector or matrix of numbers or strings : :orient flag with possible values : 1 or “r”, 2 or “c” : :N vector or matrix of numbers or strings : :k vector of integers :

Description

unique(M) returns a vector which retains the unique entries of M in ascending order.

unique(M,”r”) or unique(M,1)`returns the unique rows of `M in lexicographic ascending order.

unique(M,”c”) or unique(M,2)`returns the unique columns of `M in lexicographic ascending order.

If required the output argument k contains the position of the first encountered unique entries.

Examples

M=`round`_(2*`rand`_(20,1));

unique(M)
[N,k]=unique(M)

unique(`string`_(M))
[N,k]=unique(`string`_(M))

A = [0,0,1,1;
     0,1,1,1;
     2,0,1,1;
     0,2,2,2;
     2,0,1,1;
     0,0,1,1];
T='x'+`string`_(A);

//unique rows

[m,k]=unique(A,'r')
unique(T,'r')

//unique columns
[m,k]=unique(T,'c')
unique(A,'c')

See Also

• union extract union components of a vector
• intersect returns the vector of common values of two vectors
• gsort sorting by quick sort agorithm
• lex_sort lexicographic matrix rows sorting