Subtract vector from array along specified dimension
Math Functions / Matrices and Linear Algebra / Matrix Operations
dspmtrx3
The ArrayVector Subtract block subtracts the values in the input vector V from the values in the specified dimension of the Ndimensional input array A.
The length of the input V must be the same as the length of the specified dimension of A. The ArrayVector Subtract block subtracts each element of V from the corresponding element along that dimension of A.
Consider a 3dimensional MbyNbyP input
array A(i,j,k) and a Nby1
input vector V. When the Subtract along
dimension parameter is set to 2
,
the output of the block Y(i,j,k) is
$$Y(i,j,k)=A(i,j,k)V(j)$$
$$\begin{array}{l}1\le i\le M\\ 1\le j\le N\\ 1\le k\le P\end{array}$$
The output of the ArrayVector Subtract block is the same size as the input array, A. This block accepts real and complex floatingpoint and fixedpoint inputs.
The following diagram shows the data types used within the ArrayVector Subtract block for fixedpoint signals.
When you specify the vector V on the Main pane of the block mask, you must specify the data type and scaling properties of its elements in the Vector (V) parameter on the Data Types tab. When the vector comes in through the block port, its elements inherit their data type and scaling from the driving block.
The output of the subtractor is in the accumulator data type.
You can set the vector, accumulator, and output data types in the block dialog as discussed below.
Main Tab
Specify the dimension along which to subtract the elements of vector V from the input array A.
Specify the source of the vector, V. The
vector can come from the Input port
or
from a Dialog parameter
.
Specify the vector, V. This parameter is
visible only when you select Dialog parameter
for
the Vector (V) source parameter.
Data Types
Floatingpoint inheritance takes precedence over the data type settings defined on this pane. When inputs are floating point, the block ignores these settings, and all internal data types are floating point.
Select the rounding mode for fixedpoint operations.
The Rounding mode and Saturate on integer overflow settings have no effect on numerical results when both of the following conditions exist:
Accumulator data type is
Inherit: Inherit via internal
rule
Output data type is
Inherit: Same as
accumulator
With these data type settings, the block is effectively operating in full precision mode.
Select the overflow mode for fixedpoint operations.
Use this parameter to specify the word and fraction lengths for the elements of the vector, V. You can set this parameter to:
A rule that inherits a data type, for example, Inherit:
Same word length as input
An expression that evaluates to a valid data type,
for example, fixdt(1,16,0)
Click the Show data type assistant button to display the Data Type Assistant, which helps you set the Accumulator data type parameter.
See Specify Data Types Using Data Type Assistant (Simulink) for more information.
The Vector (V) parameter on the Data
Types pane is only visible when you select Dialog
parameter
for the Vector (V) source parameter
on the Main pane of the block mask. When
the vector comes in through the block's input port, the data type
and scaling of its elements are inherited from the driving block.
Specify the accumulator data type. See FixedPoint Data Types for illustrations depicting the use of the accumulator data type in this block. You can set this parameter to:
A rule that inherits a data type, for example, Inherit:
Inherit via internal rule
. For more information on this
rule, see Inherit via Internal Rule.
An expression that evaluates to a valid data type,
for example, fixdt(1,16,0)
Click the Show data type assistant button to display the Data Type Assistant, which helps you set the Accumulator data type parameter.
See Specify Data Types Using Data Type Assistant (Simulink) for more information.
Specify the output data type. See FixedPoint Data Types for illustrations depicting the use of the output data type in this block. You can set it to:
A rule that inherits a data type, for example, Inherit:
Same as accumulator
An expression that evaluates to a valid data type,
for example, fixdt(1,16,0)
Click the Show data type assistant button to display the Data Type Assistant, which helps you set the Output data type parameter.
See Control Signal Data Types (Simulink) for more information.
Specify the minimum value that the block should output. The
default value is []
(unspecified). Simulink^{®} software
uses this value to perform:
Simulation range checking (see Signal Ranges (Simulink))
Automatic scaling of fixedpoint data types
Specify the maximum value that the block should output. The
default value is []
(unspecified). Simulink software
uses this value to perform:
Simulation range checking (see Signal Ranges (Simulink))
Automatic scaling of fixedpoint data types
Select this parameter to prevent the fixedpoint tools from overriding the data types you specify on the block mask.
Port  Supported Data Types 

A 

V 

Output 

ArrayVector Add  DSP System Toolbox 
ArrayVector Divide  DSP System Toolbox 
ArrayVector Multiply  DSP System Toolbox 