Polybench® for biosignals / reference 1.34.1
Reads a variable or parameter and converts it to a constant numerical value at the output.

Variable To Constant


Converts the specified variable to a constant signal value at the output.

Operator ports

Output K: Floating point values
This is a Constant output, which does not output a signal, but a single value. A constant output does not have a sample frequency and is therefore recognized by Polybench to be a constant. Many calculations can be performed on constants as well as signals (or a combination of both). If an operator performs a calculation on constants only, it becomes a constant operator itself.

Constants and any other data source are allowed to be mixed without synchronization ("Synchronizer").

In a schematic, connectors that are connected to constant outputs are always colored black, while connections from other data sources may be colored differently.


Find more information about changing properties here: "Properties Viewer"

type: Address, starts with '$' sign (see "Address - how to address objects and variable parameters")
Specify the address of a variable that should be copied to the constant value at the output.

You may type or paste the address, or you may press the small button on the right to open the Address Constructor ("Address Constructor")

type: See description
The unit of the constant value. This value is optional and per default empty.

type: See description
The name of the channel that contains this constant value.

type: Word or phrase
The name of the object in the project. This name must not contain '.', '$' nor '@' characters.

For more information about the rules and usage of the Caption property, please refer to "Caption property - background and usage".

type: See description
Optional documentation of this object. If this object is an operator, the Documentation text is displayed below the operator symbol.

Variable Parameters

Find more information about Variable Parameters here: "Variable Parameters"

type: See description
Specify the address of a variable that should be copied to the constant value at the output.


If the variable does not refer to a numerical value, then the result is 0. If the variable does not refer to a valid location, then the constant value is also 0. If the variable refers to a value in a list, and that value is currently not available, then the output constant is 0 as well.

If the variable address refers to multiple, equal operators that have the same caption, so that they have the same address, then the variable that is found first is used. You cannot know from which operator that is, so please make sure that all those operators contain the same value on that address.

Please note that it may take some time before a changed variable will result in a new constant value at the output. This is because the Variable to Constant operator polls the variable at a rather slow interval rate. In the worst case the update might take a couple of 100 milliseconds.

Also please note, that a constant sample output does not behave in the same way like a signal output. Read details about this in "Timing properties of samples in a stream".