#-------------------------------------------------------------
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# to you under the Apache License, Version 2.0 (the
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# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
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# Returns Euclidian distance matrix (distances between N n-dimensional points)

m_dist = function(Matrix[Double] X) return (Matrix[Double] Y) {
    G = X %*% t(X);
    I = matrix(1, rows = nrow(G), cols = ncol(G));
    Y = -2 * (G) + t(I %*% diag(diag(G))) + t(diag(diag(G)) %*% I);
    Y = sqrt(Y);
    Y = replace(target = Y, pattern=0/0, replacement = 0);
}