Polybench® Reference
Results in the subtraction of input signal S2 from input signal S1, or: S1 - S2.

S1 - S2

Overview

Subtracts sample values of all channels from the sample values of the same channels on the other input.

Operator ports

Input S1: Floating point values

Input -S2: Floating point values

Output S1-S2: Floating point values

Properties

Find more information about changing properties here: link

Caption
type: Word or phrase
The name of the object in the project. This name must not contain '.' or '$' characters.

Every object has the Caption property. This property is very important, because it is the name by which Polybench recognizes this object.
It is allowed to give multiple objects the same name, as long as the objects are of the same type. In that case, a reference to this caption includes all the objects with the same caption.
In Polybench, every object can be addressed by an Address specifier, which starts with the dollar sign, for example: $My Page.My Object. 'My Page' would be the Caption of a page, and 'My Object' the Caption of an object on that page.

Documentation
type: See description
Optional documentation of this object.

It is good practice to write in short notes why you have used this object, and why its properties are set the way they are set. If this object is an operator, the Documentation text is displayed below the operator symbol.

Details

Case 1: equal number of channels
If both input buses contain an equal number of channels, the sample value of every channel at input S1 is subtracted from the value of the channel with the same number at input S2 and put to the same output channel.

Case 2: input with one channel
If one input bus contains one channel and the other input contains more than one channel, the sample value of the single channel input is subtracted from the value of every channel of the other input.

Case 3: unequal number of channels
If the two input buses contain an unequal number of channels, and neither has one channel, then the operator outputs no data and a warning is displayed below the symbol.

It is allowed to connect a signal that feeds back from the output to one of the inputs that originates from the output. It is however recommended to only feed back on the lower (S2) input.

It is not allowed to directly subtract signals from two different sources. You need to synchronize the signals first, using the Synchronizer (link).

The calculation is also performed on constant values (e.g. from a Constant (link); either if one of the inputs is a constant or both.