ReshapedMethods.h File Reference

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Functions
template<int Order = ColMajor>
Reshaped< Derived,... >	reshaped ()
template<int Order = ColMajor>
const Reshaped< const Derived,... >	reshaped () const
	This is the const version of reshaped(). More...
template<int Order = ColMajor, typename NRowsType , typename NColsType >
Reshaped< Derived,... >	reshaped (NRowsType nRows, NColsType nCols)
template<int Order = ColMajor, typename NRowsType , typename NColsType >
const Reshaped< const Derived,... >	reshaped (NRowsType nRows, NColsType nCols) const
	This is the const version of reshaped(NRowsType,NColsType). More...

Function Documentation

reshaped() [1/4]

template<int Order = ColMajor>

Reshaped<Derived,...> reshaped ( )

inline

Returns

an expression of *this with columns (or rows) stacked to a linear column vector

Template Parameters

Order

specifies whether the coefficients should be processed in column-major-order (ColMajor), in row-major-order (RowMajor), or follows the natural order of the nested expression (AutoOrder). The default is ColMajor.

This overloads is essentially a shortcut for A.reshaped<Order>(AutoSize,fix<1>).

• If Order==ColMajor (the default), then it returns a column-vector from the stacked columns of *this.
• If Order==RowMajor, then it returns a column-vector from the stacked rows of *this.
• If Order==AutoOrder, then it returns a column-vector with elements stacked following the storage order of *this. This mode is the recommended one when the particular ordering of the element is not relevant.

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.reshaped().transpose():" << endl << m.reshaped().transpose() << endl;
cout << "Here is m.reshaped<RowMajor>().transpose():  " << endl << m.reshaped<RowMajor>().transpose() << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.reshaped().transpose():
 7 -2  6  6  9 -6 -3  6 -5  1  0  3 -3  0  9  9
Here is m.reshaped<RowMajor>().transpose():  
 7  9 -5 -3 -2 -6  1  0  6 -3  0  9  6  6  3  9

If you want more control, you can still fall back to reshaped(NRowsType,NColsType).

See also

reshaped(NRowsType,NColsType), class Reshaped

reshaped() [2/4]

template<int Order = ColMajor>

const Reshaped<const Derived,...> reshaped ( ) const

inline

This is the const version of reshaped().

reshaped() [3/4]

template<int Order = ColMajor, typename NRowsType , typename NColsType >

Reshaped<Derived,...> reshaped ( NRowsType  nRows, NColsType  nCols  )

inline

Returns

an expression of *this with reshaped sizes.

Parameters

nRows	the number of rows in the reshaped expression, specified at either run-time or compile-time, or AutoSize
nCols	the number of columns in the reshaped expression, specified at either run-time or compile-time, or AutoSize

Template Parameters

Order	specifies whether the coefficients should be processed in column-major-order (ColMajor), in row-major-order (RowMajor), or follows the natural order of the nested expression (AutoOrder). The default is ColMajor.
NRowsType	the type of the value handling the number of rows, typically Index.
NColsType	the type of the value handling the number of columns, typically Index.

Dynamic size example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.reshaped(2, 8):" << endl << m.reshaped(2, 8) << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.reshaped(2, 8):
 7  6  9 -3 -5  0 -3  9
-2  6 -6  6  1  3  0  9

The number of rows nRows and columns nCols can also be specified at compile-time by passing Eigen::fix<N>, or Eigen::fix<N>(n) as arguments. In the later case, n plays the role of a runtime fallback value in case N equals Eigen::Dynamic. Here is an example with a fixed number of rows and columns:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.reshaped(fix<2>,fix<8>):" << endl << m.reshaped(fix<2>,fix<8>) << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.reshaped(fix<2>,fix<8>):
 7  6  9 -3 -5  0 -3  9
-2  6 -6  6  1  3  0  9

Finally, one of the sizes parameter can be automatically deduced from the other one by passing AutoSize as in the following example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.reshaped(2, AutoSize):" << endl << m.reshaped(2, AutoSize) << endl;
cout << "Here is m.reshaped<RowMajor>(AutoSize, fix<8>):" << endl << m.reshaped<RowMajor>(AutoSize, fix<8>) << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.reshaped(2, AutoSize):
 7  6  9 -3 -5  0 -3  9
-2  6 -6  6  1  3  0  9
Here is m.reshaped<RowMajor>(AutoSize, fix<8>):
 7  9 -5 -3 -2 -6  1  0
 6 -3  0  9  6  6  3  9

AutoSize does preserve compile-time sizes when possible, i.e., when the sizes of the input are known at compile time and that the other size is passed at compile-time using Eigen::fix<N> as above.

See also

class Reshaped, fix, fix<N>(int)

reshaped() [4/4]

template<int Order = ColMajor, typename NRowsType , typename NColsType >

const Reshaped<const Derived,...> reshaped ( NRowsType  nRows, NColsType  nCols  ) const

inline

This is the const version of reshaped(NRowsType,NColsType).