Function Nodes

Function nodes take the output of other nodes and change it before passing it on: inverting it, looking back at earlier bars, extending or blocking signals, counting them, or switching a state on and off.

They read from solvers, logic nodes and other function nodes, so you can chain as many as you need. Several can look back at earlier bars or carry a signal forward into later ones.

Function nodes

Node	What it does	Typical use
Inverter	Inverts its input (1 – x), separately for the Long and Short sides.	Build a condition for what you don’t want, then invert it.
Long/Short Modifier	Combines or swaps the Long and Short values with each other. The one node where the two sides interact.	Swap directions, mirror one side onto the other, or combine both sides into one value.
Lookback	Looks back over earlier bars, or shifts a signal by a number of bars.	Did a signal happen in the last 10 bars? Bring a signal from 3 bars ago to the current bar.
Signal Blocker	Lets the first signal through and blocks the ones that follow, until it is reset.	Remove duplicate signals so you don’t get unwanted extra entries.
Signal Counter	Counts signals (or bars without one) over a number of bars.	Has a condition held for the last 3 bars?
Signal Extender	Extends a signal forward for a number of bars.	Keep a one-bar crossover signal valid for the next 5 bars.
Toggle	An on/off switch, turned on and off by signals.	Systems that need to remember a state.

Adding function nodes

On the Logic tab, open the Function menu (or right-click the Logic Board) and choose a node. Connect another node’s output to its input, and its output onward.

Function nodes have the same Properties tab, Modifiers and Options tab as other nodes; each node’s page describes them. Their own settings apply to that node only.

Resetting function nodes

The Signal Blocker, Signal Counter, Signal Extender and Toggle can be reset (turned off). For example: a Signal Counter counting signals over the last 10 bars that is reset 5 bars back restarts its count there, as if counting only 5 bars. A Signal Extender that is reset stops extending. A Signal Blocker that is reset stops blocking and lets the next signal through.

Besides its Input connector, each of these nodes has a separate Reset connector, for a signal that marks when to reset. The Toggle has its own reset settings (see its page); the others share these:

Reset On

Which signals reset (turn off) the node: signals at its Input connector, at its separate Reset connector, or both. Tick as many as you need, and untick any you don’t use so the node isn’t reset by accident.

As everywhere in BloodHound, the Long output and the Short output are reset separately: a Long reset signal resets only the Long side. The “Opposite” options are the exception that crosses over, letting a Short signal reset the Long side and vice versa.

Option	Resets the node when…
Input Signal	A Long signal at the Input connector resets the Long output’s calculation; a Short signal resets the Short output’s.
Input No Signal	A bar with no Long signal at the Input resets the Long output’s calculation; a bar with no Short signal resets the Short output’s.
Reset Signal	A Long signal at the Reset connector resets the Long output’s calculation; a Short signal resets the Short output’s.
Reset No Signal	A bar with no Long signal at the Reset connector resets the Long output’s calculation; a bar with no Short signal resets the Short output’s.
Input Opposite Signal	Crosses over: a Short signal at the Input resets the Long output’s calculation, and a Long signal resets the Short output’s.
Input Opposite No Signal	A bar with no Short signal at the Input resets the Long output’s calculation; a bar with no Long signal resets the Short output’s.
Reset Opposite Signal	A Short signal at the Reset connector resets the Long output’s calculation; a Long signal resets the Short output’s.
Reset Opposite No Signal	A bar with no Short signal at the Reset connector resets the Long output’s calculation; a bar with no Long signal resets the Short output’s.