find — find indices of boolean vector or matrix true elements
[ii]=find(x [,nmax]) [i1,i2,..]=find(x [,nmax])
may be a boolean vector, a boolean matrix, a boolean hypermatrix, a "standard" matrix or hypermatrix
an integer giving the maximum number of indices to return. The default value is -1 which stands for "all". This option can be used for efficiency, to avoid searching all indices.
integer vectors of indices or empty matrices
If x is a boolean matrix,
ii=find(x) returns the vector
of indices i for which x(i) is "true". If no true element
found find returns an empty matrix.
[i1,i2,..]=find(x) returns vectors of indices i1 (for rows) and i2 (for columns),..
such that x(i1(n),i2(n),..) is "true". If no true element
found find returns empty matrices in i1,
i2, ...
if x is a standard matrix or hypermatrix find(x) is interpreted as
find(x<>0)
find([]) returns []
beers=["Desperados", "Leffe", "Kronenbourg", "Heineken"]; find(beers=="Leffe") // OK find(beers=="1664") // KO find(beers=="Foster") // KO beers=[beers, "Foster"] find(beers=="Foster") // OK A=rand(1,20); w=find(A<0.4) A(w) w=find(A>100) B=rand(1,20); w=find(B<0.4,2) //at most 2 returned values H=rand(4,3,5); //an hypermatrix [i,j,k]=find(H>0.9) H(i(1),j(1),k(1))