Eigen::VectorwiseOp

Deprecated:

since Eigen 3.3

Returns

a row (or column) vector expression representing whether all coefficients of each respective column (or row) are true. This expression can be assigned to a vector with entries of type bool.

See also

DenseBase::all()

Returns

a row (or column) vector expression representing whether at least one coefficient of each respective column (or row) is true. This expression can be assigned to a vector with entries of type bool.

See also

DenseBase::any()

returns an iterator to the first row (rowwise) or column (colwise) of the nested expression.

See also

end(), cbegin()

const version of begin()

Returns

a row (or column) vector expression of the norm of each column (or row) of the referenced expression, using Blue's algorithm. This is a vector with real entries, even if the original matrix has complex entries.

See also

DenseBase::blueNorm()

const version of begin()

const version of end()

Returns

a row (or column) vector expression representing the number of true coefficients of each respective column (or row). This expression can be assigned to a vector whose entries have the same type as is used to index entries of the original matrix; for dense matrices, this is std::ptrdiff_t .

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
Matrix<ptrdiff_t, 3, 1> res = (m.array() >= 0.5).rowwise().count();
cout << "Here is the count of elements larger or equal than 0.5 of each row:" << endl;
cout << res << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the count of elements larger or equal than 0.5 of each row:
2
2
1

See also

DenseBase::count()

const version of rbegin()

const version of rend()

returns an iterator to the row (resp. column) following the last row (resp. column) of the nested expression

See also

begin(), cend()

const version of end()

Returns

a row (or column) vector expression of the norm of each column (or row) of the referenced expression, avoiding underflow and overflow using a concatenation of hypot() calls. This is a vector with real entries, even if the original matrix has complex entries.

See also

DenseBase::hypotNorm()

Returns

a row (or column) vector expression of the norm of each column (or row) of the referenced expression. This is a vector with real entries, even if the original matrix has complex entries.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the norm of each column:" << endl << m.colwise().norm() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the norm of each column:
 0.91  1.18 0.771

See also

DenseBase::norm()

Returns

a row (or column) vector expression of the largest coefficient of each column (or row) of the referenced expression.

Warning

the size along the reduction direction must be strictly positive, otherwise an assertion is triggered.

the result is undefined if *this contains NaN.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the maximum of each column:" << endl << m.colwise().maxCoeff() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the maximum of each column:
 0.68 0.823 0.536

See also

DenseBase::maxCoeff()

Returns

a row (or column) vector expression of the mean of each column (or row) of the referenced expression.

See also

DenseBase::mean()

Returns

a row (or column) vector expression of the smallest coefficient of each column (or row) of the referenced expression.

Warning

the size along the reduction direction must be strictly positive, otherwise an assertion is triggered.

the result is undefined if *this contains NaN.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the minimum of each column:" << endl << m.colwise().minCoeff() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the minimum of each column:
-0.211 -0.605 -0.444

See also

DenseBase::minCoeff()

Returns

a row (or column) vector expression of the norm of each column (or row) of the referenced expression. This is a vector with real entries, even if the original matrix has complex entries.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the norm of each column:" << endl << m.colwise().norm() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the norm of each column:
 0.91  1.18 0.771

See also

DenseBase::norm()

Normalize in-place each row or columns of the referenced matrix.

See also

MatrixBase::normalize(), normalized()

Returns

an expression where each column (or row) of the referenced matrix are normalized. The referenced matrix is not modified.

See also

MatrixBase::normalized(), normalize()

Returns the expression where each subvector is the product of the vector other by the corresponding subvector of *this

Multiples each subvector of *this by the vector other

Returns the expression of the sum of the vector other to each subvector of *this

Adds the vector other to each subvector of *this

Returns the expression of the difference between each subvector of *this and the vector other

Substracts the vector other to each subvector of *this

Returns the expression where each subvector is the quotient of the corresponding subvector of *this by the vector other

Divides each subvector of *this by the vector other

Copies the vector other to each subvector of *this

Returns

a row (or column) vector expression of the product of each column (or row) of the referenced expression.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the product of each row:" << endl << m.rowwise().prod() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the product of each row:
 -0.134
-0.0933
  0.152

See also

DenseBase::prod()

returns a reverse iterator to the last row (rowwise) or column (colwise) of the nested expression.

See also

rend(), crbegin()

const version of rbegin()

Returns

a row or column vector expression of *this reduxed by func

The template parameter BinaryOp is the type of the functor of the custom redux operator. Note that func must be an associative operator.

Warning

the size along the reduction direction must be strictly positive, otherwise an assertion is triggered.

See also

class VectorwiseOp, DenseBase::colwise(), DenseBase::rowwise()

returns a reverse iterator to the row (resp. column) before the first row (resp. column) of the nested expression

See also

begin(), cend()

const version of rend()

Returns

an expression of the replication of each column (or row) of *this

Example:

Vector3i v = Vector3i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "v.rowwise().replicate(5) = ..." << endl;
cout << v.rowwise().replicate(5) << endl;

Output:

Here is the vector v:
 7
-2
 6
v.rowwise().replicate(5) = ...
 7  7  7  7  7
-2 -2 -2 -2 -2
 6  6  6  6  6

See also

VectorwiseOp::replicate(), DenseBase::replicate(), class Replicate

Returns

an expression of the replication of each column (or row) of *this

Example:

MatrixXi m = MatrixXi::Random(2,3);
cout << "Here is the matrix m:" << endl << m << endl;
cout << "m.colwise().replicate<3>() = ..." << endl;
cout << m.colwise().replicate<3>() << endl;

Output:

Here is the matrix m:
 7  6  9
-2  6 -6
m.colwise().replicate<3>() = ...
 7  6  9
-2  6 -6
 7  6  9
-2  6 -6
 7  6  9
-2  6 -6

See also

VectorwiseOp::replicate(Index), DenseBase::replicate(), class Replicate

Returns

a writable matrix expression where each column (or row) are reversed.

See also

reverse() const

Returns

a matrix expression where each column (or row) are reversed.

Example:

MatrixXi m = MatrixXi::Random(3,4);
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the rowwise reverse of m:" << endl << m.rowwise().reverse() << endl;
cout << "Here is the colwise reverse of m:" << endl << m.colwise().reverse() << endl;
 
cout << "Here is the coefficient (1,0) in the rowise reverse of m:" << endl
<< m.rowwise().reverse()(1,0) << endl;
cout << "Let us overwrite this coefficient with the value 4." << endl;
//m.colwise().reverse()(1,0) = 4;
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  6 -3  1
-2  9  6  0
 6 -6 -5  3
Here is the rowwise reverse of m:
 1 -3  6  7
 0  6  9 -2
 3 -5 -6  6
Here is the colwise reverse of m:
 6 -6 -5  3
-2  9  6  0
 7  6 -3  1
Here is the coefficient (1,0) in the rowise reverse of m:
0
Let us overwrite this coefficient with the value 4.
Now the matrix m is:
 7  6 -3  1
-2  9  6  0
 6 -6 -5  3

See also

DenseBase::reverse()

This is the "in place" version of VectorwiseOp::reverse: it reverses each column or row of *this.

In most cases it is probably better to simply use the reversed expression of a matrix. However, when reversing the matrix data itself is really needed, then this "in-place" version is probably the right choice because it provides the following additional benefits:

• less error prone: doing the same operation with .reverse() requires special care:

  m = m.reverse().eval(); 
  

• this API enables reverse operations without the need for a temporary

See also

DenseBase::reverseInPlace(), reverse()

Returns

a row (or column) vector expression of the squared norm of each column (or row) of the referenced expression. This is a vector with real entries, even if the original matrix has complex entries.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the square norm of each row:" << endl << m.rowwise().squaredNorm() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the square norm of each row:
0.928
 1.01
0.884

See also

DenseBase::squaredNorm()

Returns

a row (or column) vector expression of the norm of each column (or row) of the referenced expression, avoiding underflow and overflow. This is a vector with real entries, even if the original matrix has complex entries.

See also

DenseBase::stableNorm()

Returns

a row (or column) vector expression of the sum of each column (or row) of the referenced expression.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the sum of each row:" << endl << m.rowwise().sum() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the sum of each row:
 0.948
  1.15
-0.483

See also

DenseBase::sum()

This is the const version of iterator (aka read-only)

STL-like RandomAccessIterator iterator type over the columns or rows as returned by the begin() and end() methods.