For Iterator
Repeat execution of a subsystem during a time step for a specified number of iterations
- Library:
Ports & Subsystems
Description
The For Iterator block, when placed in a Subsystem
block, repeats the execution of a subsystem during the current time step until an
iteration variable exceeds the specified iteration limit. You can use this block to
implement the block diagram equivalent of a for loop in a programming
language.
The output of a For Iterator Subsystem block cannot be a function-call signal. Simulink® displays an error message when the model updates.
Ports
Input
Number of Iterations — External value for iterator variable
scalar | vector, size 1 | matrix, size 1x1
The input port accepts data of mixed numeric types.
If the input port value is non-integer, it is first truncated to an integer.
Internally, the input value is cast to an integer of the type specified for the iteration variable output port.
If no output port is specified, the input port value is cast to type
int32.If the input port value exceeds the maximum value of the output port type, the overflow wraps around.
Data Types: single | double | int8 | int16 | int32 | uint8 | uint16 | uint32
Output
Iterator value — Value of iterator variable during time step
scalar | vector, size 1 | matrix, size 1-by-1
Selecting the Show iteration variable parameter check box adds an output port to this block.
Data Types: double | int8 | int16 | int32 | uint8 | uint16 | uint32
Parameters
States when starting — Select block states between time steps
held (default) | reset
Select how to handle block states between time steps.
heldHold block states between time steps. Block state values persist across time steps.
resetReset block states to their initial values at the beginning of each time step and before the first iteration loop.
Programmatic Use
Block Parameter:
ResetStates |
| Type: character vector |
Values:
'held' | 'reset' |
Default:
'held' |
Iteration limit source — Select source for number of iterations
internal (default) | external
Select source for number of iterations.
internalValue of the Iteration limit parameter determines the number of iterations.
externalValue of the signal at the N port determines the number of iterations. The signal source must reside outside the For Iterator Subsystem block.
Dependencies
Selecting internal displays and enables the
Iteration limit parameter. Selecting
external adds an input port labeled
N.
Programmatic Use
Block Parameter:
IterationSource |
| Type: character vector |
Values:
'internal' |
'external' |
Default:
'internal' |
Iteration limit — Specify number of iterations
5 (default) | integer
Specify the number of iterations. This parameter supports storage classes.
You can define the named constant in the base workspace of the Model
Explorer as a Simulink.Parameter object
of the built-in storage class Define (custom)
type.
5Iterate blocks in the For Iterator Subsystem block
5times.- integer
Specify an integer or a named constant variable.
Dependencies
To enable this parameter, select internal
from the Iteration limit source drop-down
list.
Programmatic Use
Block Parameter:
IterationLimit |
| Type: character vector |
Values: '5'
| '<integer>' |
Default:
'5' |
Set Next i (iteration variable) externally — Control display of input port
off (default) | on
Control display of an input port.
- off
Remove input port.
- on
Add input port labeled Next_i for connecting to an external iteration variable source. The value of the input at the current iteration is used as the value of the iteration variable at the next iteration.
Dependencies
To enable this parameter, select the Show iteration variable parameter which also displays an output port labeled 1:N.
Programmatic Use
Block Parameter:
ExternalIncrement |
| Type: character vector |
Values:
'off' | 'on' |
Default:
'off' |
Show iteration variable — Control display of output port
on (default) | off
Control the display of an output port with the current iterator value for a loop.
- on
Add output port labeled 1:N to the For Iterator block.
- off
Remove output port.
Dependencies
Selecting this parameter enables the Set next i (iteration variable) externally parameter.
Programmatic Use
Block Parameter:
ShowIterationPort |
| Type: character vector |
Value: 'on'
| 'off' |
Default:
'on' |
Index mode — Select initial iteration number
One-based (default) | Zero-based
Select an initial iteration number of 0 or
1.
One-basedIteration number starts at one.
Zero-basedIteration number starts at zero.
Programmatic Use
Block Parameter:
IndexMode |
| Type: character vector |
Values:
'One-based' |
'Zero-based' |
Default:
'One-based' |
Iteration variable data type — Select data type
int32 (default) | uint32 | int16 | uint16 | int8 | uint8 | double
Set the data type for the iteration value output from the iteration number port.
int32Set data type to
int32.uint32Set data type to
uint32.int16Set data type to
int16.uint16Set data type to
uint16.int8Set data type to
int8.uint8Set data type to
uint8.doubleSet data type to
double.
Programmatic Use
Block Parameter:
IterationVariableDataType |
| Type: character vector |
Value:
'int32' |
'uint32'|'int16' |
'uint16'|'int8' |
'uint8'|'double' |
Default:
'int32' |
