Copy or invert one scalar input, or collapse one nonscalar input
Math Operations
The Product of Elements block inputs one scalar, vector, or matrix. You can use the block to:
Copy a scalar input unchanged
Invert a scalar input (divide 1 by it)
Collapse a vector or matrix to a scalar by multiplying together all elements or taking successive inverses of the elements
Collapse a matrix to a vector by multiplying together the elements of each row or column or taking successive inverses of the elements of each row or column
The Product of Elements block is functionally a Product block that has two preset parameter values:
Multiplication: Elementwise(.*)
Number of inputs: *
Setting nondefault values for either of those parameters can change a Product of Elements block to be functionally equivalent to a Product block or a Divide block. See the documentation of those two blocks for more information.
The Product of Elements block uses the following algorithms to perform elementwise operations on inputs of floatingpoint, builtin integer, and fixedpoint types:
Input  ElementWise Operation  Algorithm 

Real scalar,  Multiplication  y = u 
Division  y = 1/u  
Real vector or matrix, with elements  Multiplication  y = u1*u2*u3*...*uN 
Division  y = ((((1/u1)/u2)/u3).../uN)  
Complex scalar,  Multiplication  y = u 
Division  y = 1/u  
Complex vector or matrix, with elements  Multiplication  y = u1*u2*u3*...*uN 
Division  y = ((((1/u1)/u2)/u3).../uN) 
If the specified dimension for elementwise multiplication or division is a row or column of a matrix, the algorithm applies to that row or column. For example, consider the following modelmodel:
The top Product of Elements block collapses the matrix input to a scalar by taking successive inverses of the four elements:
y = ((((1/2+i)/3)/4i)/5)
The bottom Product of Elements block collapses the matrix input to a vector by taking successive inverses along the second dimension:
y(1) = ((1/2+i)/3)
y(2) = ((1/4i)/5)
The Product of Elements block has the same parameters and dialog
box as the Product block, plus
the parameter Multiply over, which has the default
value All dimensions
:
If you set Multiply over to Specified
dimension
, the Dimension parameter
appears.
To copy, invert, or collapse one input to create an output, you can use the Product of Elements block with default values for all parameters except Number of inputs, Multiply over, and Dimension. These values can require change. For other capabilities, see the Product block documentation, which also describes the Signal Attributes Pane of the Product of Elements block.
This parameter is the same as in the Product block, but the
value must be *
(the default), 1
,
or /
to achieve the behavior of a Product
of Elements block.
Parameter Value  Block Behavior  Block Icon 

* or 1 
For more information, see Algorithm.  
/ 
For more information, see Algorithm. 
This parameter appears only when Multiplication is Elementwise(.*)
and Number
of inputs is *
, 1
,
or /
. The parameter affects only a matrix
input. The possible values are:
All dimensions
— The block
outputs a scalar that is the product of all matrix elements, or the
result of taking successive inverses of the elements, depending on
the value of Number of inputs.
Specified dimension
— The
block outputs a vector, in which the composition depends on the value
of the Dimension parameter.
This parameter appears only when the Multiply over parameter
appears and is set to Specified dimension
.
The parameter affects only a matrix input, and must be 1 for a scalar
or vector input. The possible values are:
1
— Output a vector that
contains an element for each column of the input matrix.
2
— Output a vector that
contains an element for each row of the input matrix.
Each element of the output vector contains the product of all elements in the corresponding column or row of the input matrix, or the result of taking successive inverses of those elements. The output vector depends on the value of Number of inputs:
*
or 1
Multiply the values of the column or row elements.
/
Take successive inverses of the column or row elements. For more information, see Algorithm.
This table shows the output of the Product of Elements block for example inputsexample inputs using default block parameter values, except as shown in the table.
Parameter Values  Examples 

Multiplication: Number
of inputs: 

Multiplication: Number
of inputs: 

Multiplication: Number
of inputs: 

Multiplication: Number
of inputs: Multiply
over: 

Multiplication: Number
of inputs: Multiply over: Dimension: 

Multiplication: Number
of inputs: Multiply
over: Dimension: 
