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C++ VectorSet::next_element方法代码示例

本文整理汇总了C++中VectorSet::next_element方法的典型用法代码示例。如果您正苦于以下问题:C++ VectorSet::next_element方法的具体用法?C++ VectorSet::next_element怎么用?C++ VectorSet::next_element使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在VectorSet的用法示例。


在下文中一共展示了VectorSet::next_element方法的3个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: color_general_colpack

void color_general_colpack(
    VectorSet&        pattern ,
    const VectorSize&       row     ,
    const VectorSize&       col     ,
    CppAD::vector<size_t>&  color   )
{   size_t i, j, k;
    size_t m = pattern.n_set();
    size_t n = pattern.end();

    // Determine number of non-zero entries in each row
    CppAD::vector<size_t> n_nonzero(m);
    size_t n_nonzero_total = 0;
    for(i = 0; i < m; i++)
    {   n_nonzero[i] = 0;
        pattern.begin(i);
        j = pattern.next_element();
        while( j != pattern.end() )
        {   n_nonzero[i]++;
            j = pattern.next_element();
        }
        n_nonzero_total += n_nonzero[i];
    }

    // Allocate memory and fill in Adolc sparsity pattern
    CppAD::vector<unsigned int*> adolc_pattern(m);
    CppAD::vector<unsigned int>  adolc_memory(m + n_nonzero_total);
    size_t i_memory = 0;
    for(i = 0; i < m; i++)
    {   adolc_pattern[i]    = adolc_memory.data() + i_memory;
        adolc_pattern[i][0] = n_nonzero[i];
        pattern.begin(i);
        j = pattern.next_element();
        k = 1;
        while(j != pattern.end() )
        {   adolc_pattern[i][k++] = j;
            j = pattern.next_element();
        }
        CPPAD_ASSERT_UNKNOWN( k == 1 + n_nonzero[i] );
        i_memory += k;
    }
    CPPAD_ASSERT_UNKNOWN( i_memory == m + n_nonzero_total );

    // Must use an external routine for this part of the calculation because
    // ColPack/ColPackHeaders.h has as 'using namespace std' at global level.
    cppad_colpack_general(color, m, n, adolc_pattern);

    return;
}
开发者ID:CSCsw,项目名称:CppAD,代码行数:48,代码来源:color_general.hpp

示例2: color_general_cppad

void color_general_cppad(
    VectorSet&        pattern ,
    const VectorSize&       row     ,
    const VectorSize&       col     ,
    CppAD::vector<size_t>&  color   )
{   size_t i, j, k, ell, r;

    size_t K = row.size();
    size_t m = pattern.n_set();
    size_t n = pattern.end();

    CPPAD_ASSERT_UNKNOWN( size_t( col.size() )   == K );
    CPPAD_ASSERT_UNKNOWN( size_t( color.size() ) == m );

    // We define the set of rows, columns, and pairs that appear
    // by the set ( row[k], col[k] ) for k = 0, ... , K-1.

    // initialize rows that appear
    CppAD::vector<bool> row_appear(m);
    for(i = 0; i < m; i++)
        row_appear[i] = false;

    // rows and columns that appear
    VectorSet c2r_appear, r2c_appear;
    c2r_appear.resize(n, m);
    r2c_appear.resize(m, n);
    for(k = 0;  k < K; k++)
    {   CPPAD_ASSERT_UNKNOWN( pattern.is_element(row[k], col[k]) );
        row_appear[ row[k] ] = true;
        c2r_appear.add_element(col[k], row[k]);
        r2c_appear.add_element(row[k], col[k]);
    }

    // for each column, which rows are non-zero and do not appear
    VectorSet not_appear;
    not_appear.resize(n, m);
    for(i = 0; i < m; i++)
    {   pattern.begin(i);
        j = pattern.next_element();
        while( j != pattern.end() )
        {   if( ! c2r_appear.is_element(j , i) )
                not_appear.add_element(j, i);
            j = pattern.next_element();
        }
    }

    // initial coloring
    color.resize(m);
    ell = 0;
    for(i = 0; i < m; i++)
    {   if( row_appear[i] )
            color[i] = ell++;
        else	color[i] = m;
    }
    /*
    See GreedyPartialD2Coloring Algorithm Section 3.6.2 of
    Graph Coloring in Optimization Revisited by
    Assefaw Gebremedhin, Fredrik Maane, Alex Pothen

    The algorithm above was modified (by Brad Bell) to take advantage of the
    fact that only the entries (subset of the sparsity pattern) specified by
    row and col need to be computed.
    */
    CppAD::vector<bool> forbidden(m);
    for(i = 1; i < m; i++) // for each row that appears
        if( color[i] < m )
        {
            // initial all colors as ok for this row
            // (value of forbidden for ell > initial color[i] does not matter)
            for(ell = 0; ell <= color[i]; ell++)
                forbidden[ell] = false;

            // -----------------------------------------------------
            // Forbid colors for which this row would destroy results:
            //
            // for each column that is non-zero for this row
            pattern.begin(i);
            j = pattern.next_element();
            while( j != pattern.end() )
            {   // for each row that appears with this column
                c2r_appear.begin(j);
                r = c2r_appear.next_element();
                while( r != c2r_appear.end() )
                {   // if this is not the same row, forbid its color
                    if( (r < i) & (color[r] < m) )
                        forbidden[ color[r] ] = true;
                    r = c2r_appear.next_element();
                }
                j = pattern.next_element();
            }


            // -----------------------------------------------------
            // Forbid colors that destroy results needed for this row.
            //
            // for each column that appears with this row
            r2c_appear.begin(i);
            j = r2c_appear.next_element();
            while( j != r2c_appear.end() )
            {   // For each row that is non-zero for this column
//.........这里部分代码省略.........
开发者ID:CSCsw,项目名称:CppAD,代码行数:101,代码来源:color_general.hpp

示例3: zero

size_t ADFun<Base>::SparseJacobianRev(
	const VectorBase&     x           ,
	VectorSet&            p           ,
	VectorBase&           jac         ,
	sparse_jacobian_work& work        )
{
	using   CppAD::vectorBool;
	size_t i, j, k, ell;

	CppAD::vector<size_t>& row(work.user_row);
	CppAD::vector<size_t>& col(work.user_col);
	CppAD::vector<size_t>& sort_row(work.sort_row);
	CppAD::vector<size_t>& color(work.color);

	size_t m = Range();
	size_t n = Domain();

	// some values
	const Base zero(0);
	const Base one(1);

	// check VectorBase is Simple Vector class with Base type elements
	CheckSimpleVector<Base, VectorBase>();

	CPPAD_ASSERT_UNKNOWN( size_t(x.size()) == n );
	CPPAD_ASSERT_UNKNOWN (color.size() == m || color.size() == 0 );

	// number of components of Jacobian that are required
	size_t K = size_t(jac.size());
	CPPAD_ASSERT_UNKNOWN( row.size() == K+1 );
	CPPAD_ASSERT_UNKNOWN( col.size() == K+1 );
	CPPAD_ASSERT_UNKNOWN( row[K] == m );
	CPPAD_ASSERT_UNKNOWN( col[K] == n );

	// Point at which we are evaluating the Jacobian
	Forward(0, x);

	if( color.size() == 0 )
	{	CPPAD_ASSERT_UNKNOWN( p.n_set() ==  m );
		CPPAD_ASSERT_UNKNOWN( p.end() ==  n );

		// rows and columns that are in the returned jacobian
		VectorSet r_used, c_used;
		r_used.resize(n, m);
		c_used.resize(m, n);
		k = 0;
		while( k < K )
		{	CPPAD_ASSERT_UNKNOWN( 
				row[sort_row[k]] < m && col[sort_row[k]] < n 
			);
			CPPAD_ASSERT_UNKNOWN( 
				k == 0 || row[sort_row[k-1]] <= row[sort_row[k]] 
			);
			CPPAD_ASSERT_KNOWN(
				p.is_element(row[sort_row[k]], col[sort_row[k]]) ,
				"SparseJacobianReverse: "
				"an (row, col) pair is not in sparsity pattern."
			);
			r_used.add_element(col[sort_row[k]], row[sort_row[k]]);
			c_used.add_element(row[sort_row[k]], col[sort_row[k]]);
			k++;
		}
	
		// given a column index, which rows are non-zero and not used
		VectorSet not_used;
		not_used.resize(n, m);
		for(i = 0; i < m; i++)
		{	p.begin(i);
			j = p.next_element();
			while( j != p.end() )
			{	if( ! r_used.is_element(j , i) )
					not_used.add_element(j, i);
				j = p.next_element();
			}
		}
	
		// initial coloring
		color.resize(m);
		for(i = 0; i < m; i++)
			color[i] = i;
	
		// See GreedyPartialD2Coloring Algorithm Section 3.6.2 of
		// Graph Coloring in Optimization Revisited by
		// Assefaw Gebremedhin, Fredrik Maane, Alex Pothen
		vectorBool forbidden(m);
		for(i = 1; i < m; i++)
		{
			// initial all colors as ok for this row
			// (value of forbidden for ell > i does not matter)
			for(ell = 0; ell <= i; ell++)
				forbidden[ell] = false;
	
			// -----------------------------------------------------
			// Forbid colors for which this row would destroy results 
			// for each column that is non-zero for this row
			p.begin(i);
			j = p.next_element();
			while( j != p.end() )
			{	// for each row that this column uses
				r_used.begin(j);
//.........这里部分代码省略.........
开发者ID:bubuker,项目名称:keggle_santa,代码行数:101,代码来源:sparse_jacobian.hpp


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