mirror of
https://github.com/SoftFever/OrcaSlicer.git
synced 2025-10-23 00:31:11 -06:00
2ae2672ee9
Fixing dep build script on Windows and removing some warnings. Use bundled igl by default. Not building with the dependency scripts if not explicitly stated. This way, it will stay in Fix the libigl patch to include C source files in header only mode.
77 lines
2.2 KiB
C++
77 lines
2.2 KiB
C++
// This file is part of libigl, a simple c++ geometry processing library.
|
|
//
|
|
// Copyright (C) 2015 Olga Diamanti, Alec Jacobson
|
|
//
|
|
// This Source Code Form is subject to the terms of the Mozilla Public License
|
|
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
|
|
// obtain one at http://mozilla.org/MPL/2.0/.
|
|
#include "nchoosek.h"
|
|
#include <cmath>
|
|
#include <cassert>
|
|
|
|
IGL_INLINE double igl::nchoosek(const int n, const int k)
|
|
{
|
|
if(k>n/2)
|
|
{
|
|
return nchoosek(n,n-k);
|
|
}else if(k==1)
|
|
{
|
|
return n;
|
|
}else
|
|
{
|
|
double c = 1;
|
|
for(int i = 1;i<=k;i++)
|
|
{
|
|
c *= (((double)n-k+i)/((double)i));
|
|
}
|
|
return std::round(c);
|
|
}
|
|
}
|
|
|
|
template < typename DerivedV, typename DerivedU>
|
|
IGL_INLINE void igl::nchoosek(
|
|
const Eigen::MatrixBase<DerivedV> & V,
|
|
const int k,
|
|
Eigen::PlainObjectBase<DerivedU> & U)
|
|
{
|
|
using namespace Eigen;
|
|
if(V.size() == 0)
|
|
{
|
|
U.resize(0,k);
|
|
return;
|
|
}
|
|
assert((V.cols() == 1 || V.rows() == 1) && "V must be a vector");
|
|
U.resize(nchoosek(V.size(),k),k);
|
|
int running_i = 0;
|
|
int running_j = 0;
|
|
Matrix<typename DerivedU::Scalar,1,Dynamic> running(1,k);
|
|
int N = V.size();
|
|
const std::function<void(int,int)> doCombs =
|
|
[&running,&N,&doCombs,&running_i,&running_j,&U,&V](int offset, int k)
|
|
{
|
|
if(k==0)
|
|
{
|
|
U.row(running_i) = running;
|
|
running_i++;
|
|
return;
|
|
}
|
|
for (int i = offset; i <= N - k; ++i)
|
|
{
|
|
running(running_j) = V(i);
|
|
running_j++;
|
|
doCombs(i+1,k-1);
|
|
running_j--;
|
|
}
|
|
};
|
|
doCombs(0,k);
|
|
}
|
|
|
|
#ifdef IGL_STATIC_LIBRARY
|
|
// Explicit template instantiation
|
|
template void igl::nchoosek<Eigen::Matrix<int, -1, 1, 0, -1, 1>, Eigen::Matrix<int, -1, -1, 0, -1, -1> >(Eigen::MatrixBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> > const&, int, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, -1, 0, -1, -1> >&);
|
|
#if EIGEN_VERSION_AT_LEAST(3,3,0)
|
|
#else
|
|
template void igl::nchoosek<Eigen::CwiseNullaryOp<Eigen::internal::linspaced_op<int, true>, Eigen::Matrix<int, -1, 1, 0, -1, 1> >, Eigen::Matrix<int, -1, -1, 0, -1, -1> >(Eigen::MatrixBase<Eigen::CwiseNullaryOp<Eigen::internal::linspaced_op<int, true>, Eigen::Matrix<int, -1, 1, 0, -1, 1> > > const&, int, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, -1, 0, -1, -1> >&);
|
|
#endif
|
|
|
|
#endif
|