Dear all,
I would like to create a binary matrix (say matrix B) using
the existing information from current matrix A.
Specifically, for each cell (i,j) of matrix B, I want to
replace its value with 1 if the value of the corresponding
cell (i,j) of matrix A is within its k-th nearest neighbors
value; and 0 otherwise.
I only can get to the point where replacing each cell of
matrix B to 1 if the value of the corresponding cell of
matrix A is < THRESHOLD. Below is what am currently
experimenting with. If I can get any tips how to efficiently
improve the current code and correctly handle this, I
greatly appreciate it.
Thanks,
Susan
********
local N=_N
mkmat var1-var100, matrix(DistMatrix)
matrix AAA=DistMatrix
mkmat _all, matrix(A)
matrix B=J(`N',`N',0)
mata: mata clear
mata:
void underbar(string scalar A,
real scalar thresh)
{
real matrix B
real scalar i
B = (st_matrix(A) :< thresh)
for(i=1; i<=rows(B); i++) {
B[i,i] = 0
}
st_matrix("B", B)
}
end
mat list A
mata: underbar ("A", 50)
matrix list B
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