IC

Set initial value of signal

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  • Library:

  • Simulink / Signal Attributes

  • IC block

Description

The IC block sets the initial condition of the signal at its input port, for example, the value of the signal at the simulation start time (tstart). To do so, the block outputs the specified initial condition when you start the simulation, regardless of the actual value of the input signal. Thereafter, the block outputs the actual value of the input signal.

The IC block is useful for providing an initial guess for the algebraic state variables in a loop. For more information, see Algebraic Loop Concepts.

Behavior for Nonzero Sample Time Offset

If an IC block has a nonzero sample time offset (toffset), the IC block outputs its initial value at time t,

t = n * tperiod + toffset

where n is the smallest integer such that t ≥ tstart.

That is, the IC block outputs its initial value the first-time blocks with sample time [tperiod, toffset] execute, which can be after tstart.

Ports

Input

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Input signal, specified as a scalar, vector, matrix, or N-D array. The block sets the initial condition of this signal to the Initial value you specify.

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

Output

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Output signal provided as the Initial value you specify, followed by the actual values of the input signal. See Behavior for Nonzero Sample Time Offset for more information.

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

Parameters

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Specify the initial value of the input signal as a finite, real-valued scalar, vector, matrix, or N-D array. The value must be a scalar, or have the same dimensions as the input signal.

Programmatic Use

Block Parameter: Value
Type: character vector
Values: scalar | vector | matrix | N-D array
Default: '1'

Specify the sample time as a value other than -1. For more information, see Specify Sample Time.

Dependencies

This parameter is not visible unless it is explicitly set to a value other than -1. To learn more, see Blocks for Which Sample Time Is Not Recommended.

Programmatic Use

Block Parameter: SampleTime
Type: character vector
Values: scalar or vector
Default: '-1'

Model Examples

Simulation of a Bouncing Ball

Simulation of a Bouncing Ball

Use two different approaches to modeling a bouncing ball using Simulink®.

Open Model
Friction Model with Hard Stops

Friction Model with Hard Stops

Model friction one way in Simulink®. The two integrators in the model calculate the velocity and position of the system, which is then used in the Friction Model to calculate the friction force.

Open Model

Block Characteristics

Data Types

Boolean | double | enumerated | fixed point | integer | single

Direct Feedthrough

yes

Multidimensional Signals

yes

Variable-Size Signals

no

Zero-Crossing Detection

no

Extended Capabilities

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

See Also

Topics

Introduced before R2006a

Simulink Documentation

Support