lsst.geom 22.0.1-7-g55b2fe3+ad2a344541
BinomialMatrix.cc
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1// -*- LSST-C++ -*-
2/*
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4 * This product includes software developed by the LSST Project
5 * (https://www.lsst.org).
6 * See the COPYRIGHT file at the top-level directory of this distribution
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22
24
25namespace lsst { namespace geom { namespace polynomials {
26
27BinomialMatrix::BinomialMatrix(int nMax) : _matrix(Eigen::MatrixXd::Zero(nMax + 1, nMax + 1)) {
28 _matrix.col(0).setConstant(1);
29 _matrix.diagonal().setConstant(1);
30 for (int i = 2; i <= nMax; ++i) {
31 _matrix(i, 0) = 1.0;
32 _matrix(i, i) = 1.0;
33 for (int j = 1; j < i; ++j) {
34 _matrix(i, j) = _matrix(i - 1, j - 1) *
35 (static_cast<double>(i) / static_cast<double>(j));
36 }
37 }
38}
39
40}}} // namespace lsst::geom::polynomials
BinomialMatrix(int nMax)
Construct an object that can compute binomial coefficients with up to and including the given value.