/usr/include/ITK-4.9/vnl/vnl_rank.h is in libinsighttoolkit4-dev 4.9.0-4ubuntu1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 | // This is core/vnl/vnl_rank.h
#ifndef vnl_rank_h_
#define vnl_rank_h_
//:
// \file
// \author Peter Vanroose, Leuven
// \date 27 March 2003
// \brief Direct computation of the rank of a matrix, without using svd
//
// The (row) rank of a matrix is its number of linearly independent rows.
// This turns out to be equal to the number of linearly independent columns,
// i.e., the column rank, so it is just called the rank of the matrix.
// This can be computed by row-reducing (or column-reducing) the matrix
// and then counting the number of non-zero rows (or columns).
#include <vnl/vnl_matrix.h>
typedef enum { vnl_rank_row, vnl_rank_column, vnl_rank_both } vnl_rank_type;
typedef enum { vnl_rank_pivot_one, vnl_rank_pivot_all } vnl_rank_pivot_type;
//: Returns the rank of a matrix
// By default, the row rank of the matrix is determined.
// Specify vnl_rank_column to obtain the column rank.
//
// \relatesalso vnl_matrix
template <class T>
unsigned int vnl_rank(vnl_matrix<T> const& mat, vnl_rank_type = vnl_rank_both);
//: Row reduce a matrix.
// First try to use 1 or -1 as pivot element in each row, to avoid divisions;
// then use any nonzero element as candidate pivot.
// Repeat this process until the matrix does not change any more.
// At that point, the matrix spans the same row space as before and contains
// as many zeros as possible.
//
// When specifying vnl_rank_pivot_one is given as second argument,
// only elements with value 1 or -1 are used as candidate pivot elements.
//
// Note that for integer matrices, the resulting matrix is still integer,
// and is guaranteed to be row equivalent with the original matrix.
//
// \relatesalso vnl_matrix
//
template <class T>
vnl_matrix<T> vnl_rank_row_reduce(vnl_matrix<T> const& mat,
vnl_rank_pivot_type = vnl_rank_pivot_all);
//: Column reduce a matrix.
//
// \relatesalso vnl_matrix
//
template <class T>
vnl_matrix<T> vnl_rank_column_reduce(vnl_matrix<T> const& mat,
vnl_rank_pivot_type = vnl_rank_pivot_all);
//: Row and column reduce a matrix.
// Perform both row reduction and column reduction on a matrix.
// The resulting matrix will in general no longer span the same row space
// (or column space) as the original matrix, but the rank will not have
// changed, and the number of nonzero elements will be minimal (viz at most
// one per row and one per column).
//
// \relatesalso vnl_matrix
//
template <class T>
vnl_matrix<T> vnl_rank_row_column_reduce(vnl_matrix<T> const& mat,
vnl_rank_pivot_type = vnl_rank_pivot_all);
#define VNL_RANK_INSTANTIATE(T) extern "please #include vnl/vnl_rank.txx instead"
#endif // vnl_rank_h_
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