Permute Matrix

Reorder matrix rows or columns

• Library:

• DSP System Toolbox / Math Functions / Matrices and Linear Algebra / Matrix Operations

• 

Description

The Permute Matrix block reorders the rows or columns of an M-by-N input matrix A as specified by indexing input P.

Ports

Input

A — Input matrix

scalar | vector | matrix

Input matrix, specified as a scalar, vector, or matrix.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | fixed point | enumerated

P — Index matrix

scalar | vector

Index matrix, specified as a scalar or vector.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | enumerated

Output

Port_1 — Output signal

vector | matrix

Output signal, specified as a vector or matrix.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | fixed point | enumerated

Parameters

Permute — Permute method

Columns (default) | Rows

Method of constructing the output matrix by permuting rows or columns of the input.

When the Permute parameter is set to:

• Rows –– The block uses the rows of A to create a matrix that has the same column dimension. Input P is a length-L vector whose elements determine where each row from A must be placed in the L-by-N output matrix.

  y = [A(P(1),:) ; A(P(2),:) ; A(P(3),:) ; ... ; A(P(end),:)] % Equivalent MATLAB code 

  For row permutation, the block treats the length-M unoriented vector input at the port A as an M-by-1 matrix.

• Columns –– The block uses the columns of A to create a matrix that has the same row dimension. Input P is a length-L vector whose elements determine where each column from A must be placed in the M-by-L output matrix.

  % Equivalent MATLAB code y = [A(:,P(1)) A(:,P(2)) A(:,P(3)) ... A(:,P(end))] 

  For column permutation, the block treats the length-N unoriented vector input at port A as a 1-by-N matrix.

Index mode — Index mode

Zero-based (default) | One-based

When set to One-based, a value of 1 in the permutation vector P refers to the first row or column of the input matrix A. When set to Zero-based, a value of 0 in P refers to the first row or column of A.

Invalid permutation index — Response to an invalid index value

Clip index (default) | Clip and warn | Generate error

Response to an invalid index value. When an index value in input P references a nonexistent row or column of matrix A, the block reacts as specified in this parameter. These options are available:

• Clip index –– Clip the index to the nearest valid value (1 or M for row permutation and 1 or N for column permutation) and do not issue an alert. Example: For a 3-by-7 input matrix, a column index of 9 is clipped to 7 and a row index of -2 is clipped to 1.

• Clip and warn –– Display a warning message in the MATLAB^® Command Window and clip the index as described in the preceding bullet.

• Generate error –– Display an error dialog box and terminate the simulation.

Tunable: Yes

Error when length of P is not equal to Permute dimension size — Error message for P length

off (default) | on

Option to display an error dialog box and terminate the simulation when the length of the permutation vector P is not equal to the number of rows or columns of the input matrix A.

You can choose to open an error dialog box and terminate the simulation by setting this parameter to on.

Model Examples

Permute Matrix by Row or Column

Simulink^® model example that shows how to permute a matrix by rows or columns.

Autoscaling and Curve Fitting

The application envisioned for this example is automatic lane tracking on a road. We will show how to fit a polynomial to noisy data representing the lane boundary of the road ahead of a vehicle.

Block Characteristics

Data Types	Boolean | double | enumerated | fixed point | integer | single
Direct Feedthrough	no
Multidimensional Signals	no
Variable-Size Signals	no
Zero-Crossing Detection	no

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using Simulink® Coder™.

Generated code relies on memcpy or memset functions (string.h) under certain conditions.

Fixed-Point Conversion
Design and simulate fixed-point systems using Fixed-Point Designer™.