MATMUL
======

Matrix Multiplication



Block Screenshot
~~~~~~~~~~~~~~~~





Contents
~~~~~~~~


+ `Matrix Multiplication`_
  +

    + `Palette`_
    + `Description`_
    + `Dialog box`_
    + `Example`_
    + `Default properties`_
    + `Interfacing function`_
    + `Computational function`_
    + `See also`_





Palette
~~~~~~~


+ `Matrix operation palette`_




Description
~~~~~~~~~~~

The MATMUL block computes the multiplication of an the first input
matrix by the second input matrix/scalar. When the **Multiplication
rule** parameter is set to:


+ **1**, the block computes the matrix product. The number of rows of
  the first matrix must be equal to the number of columns of the second
  matrix. The output is a matrix where the number of rows is equal to
  that of the first input matrix and the number of columns is equal to
  that of the second input matrix.
+ **2**, the block computes the matrix element-wise product. The
  matrices must be of the same sizes. The output is a matrix of the same
  size that the input matrices.
+ **3**, the block computes the matrix-scalar product. The output is a
  matrix of the same size that input matrix.


For integer inputs, when overflow occurs the block three different
forms of results :

1- A normal non saturated result. By example, if type is int8 and the
result 128, the block output value will be -128.

2- A saturated result. For the previous example the block output value
will be 127.

3- An error message warning the user about the overflow.

The user can select one of these three forms by setting the **Do on
Overflow** field to 0,1 or 2.





Dialog box
~~~~~~~~~~






+ **Datatype(1=real double 2=Complex)** It indicates the type of the
  output. It support only the two types double (1) and complex (2). If
  we input another entry in this label xcos will print the message
  "Datatype is not supported". Properties : Type 'vec' of size 1.
+ **Multiplication rule (1= * 2= .* 3=scalar)** Select multiplication
  rule. See description for more information. Properties : Type 'vec' of
  size 1.
+ **Do on Overflow(0=Nothing 1=Saturate 2=Error)** When this parameter
  is set to zero the result is similar to a normal multiplication of two
  integer matrix. When it is set to 1, on overflow the block saturate
  the result. When it is set to 2, on overflow an error message box
  appears. For double or complex inputs this parameter is ignored.
  Properties : Type 'vec' of size 1.




Example
~~~~~~~


::

    A=[1 2 3;4 5 6]
    B=[9 8 7 6;5 4 3 2;9 7 5 3]
    y=[46 37 28 19;115 94 73 52]




Default properties
~~~~~~~~~~~~~~~~~~


+ **always active:** no
+ **direct-feedthrough:** yes
+ **zero-crossing:** no
+ **mode:** no
+ **regular inputs:** **- port 1 : size [-1,-2] / type 1** **- port 2
  : size [-2,-3] / type 1**
+ **regular outputs:** **- port 1 : size [-1,-3] / type 1**
+ **number/sizes of activation inputs:** 0
+ **number/sizes of activation outputs:** 0
+ **continuous-time state:** no
+ **discrete-time state:** no
+ **object discrete-time state:** no
+ **name of computational function:** matmul_m




Interfacing function
~~~~~~~~~~~~~~~~~~~~


+ SCI/modules/scicos_blocks/macros/MatrixOp/MATMUL.sci




Computational function
~~~~~~~~~~~~~~~~~~~~~~


+ SCI/modules/scicos_blocks/src/c/matmul_m.c
+ SCI/modules/scicos_blocks/src/c/matzmul_m.c
+ SCI/modules/scicos_blocks/src/c/matmul2_m.c
+ SCI/modules/scicos_blocks/src/c/matzmul2_m.c




See also
~~~~~~~~


+ `INTMUL - Integer Matrix Multiplication (xcos Block)`_
+ `MATDIV - Matrix Division (xcos Block)`_
+ `MATBKSL - Left Matrix Division (xcos Block)`_
+ `MATEXPM - Matrix Exponential (xcos Block)`_
+ `SUMMATION - Matrix Summation (xcos Block)`_


.. _INTMUL - Integer Matrix Multiplication (xcos Block): INTMUL.html
.. _Matrix operation palette: Matrix_pal.html
.. _MATBKSL - Left Matrix Division (xcos Block): MATBKSL.html
.. _MATEXPM - Matrix Exponential (xcos Block): MATEXPM.html
.. _Palette: MATMUL.html#Palette_MATMUL
.. _Default properties: MATMUL.html#Defaultproperties_MATMUL
.. _SUMMATION - Matrix Summation (xcos Block): SUMMATION.html
.. _Description: MATMUL.html#Description_MATMUL
.. _Computational function: MATMUL.html#Computationalfunction_MATMUL
.. _MATDIV - Matrix Division (xcos Block): MATDIV.html
.. _Example: MATMUL.html
.. _Interfacing function: MATMUL.html#Interfacingfunction_MATMUL
.. _Dialog box: MATMUL.html#Dialogbox_MATMUL
.. _See also: MATMUL.html#Seealso_MATMUL