Subtract
Element-wiseCore Math
The Subtract node computes A − B element-wise, or subtracts a constant from every element. It is fundamental for computing price differences, indicator divergence (price − MA), spread between two instruments, mean-demeaning before variance computation, and any baseline or offset removal operation in a processing pipeline.
Algorithm
- ▸Array − Array: output[i] = A[i] − B[i]
- ▸Array − Constant: output[i] = A[i] − numericB
- ▸Either operand null → null output
Parameters
| Name | Type | Default | Description |
|---|---|---|---|
| useNumericB | boolean | false | Subtract a constant instead of a second array. |
| numericB | number | 0 | The constant to subtract when useNumericB is enabled. |
Inputs & Outputs
| Port | Type | Description |
|---|---|---|
| Inputs | ||
| input1 | number[] | Primary input array A |
| input2 | number[] | Secondary input array B (ignored when useNumericB is true) |
| Outputs | ||
| values | number | null | Computed value at each bar; null before the warmup period completes |
| timestamps | number[] | Bar timestamps (UNIX ms), aligned 1-to-1 with values |
Live mode: In live streaming mode the node updates only the last bar in-place rather than recalculating the full array, keeping CPU usage minimal during real-time data feeds.
Use Cases
MA Deviation / Oscillator
Subtract a 20-period moving average from price to produce a centered oscillator showing how far price is from its mean.
MACD Histogram
Subtract the signal line from the MACD line to construct the MACD histogram — the primary entry trigger in histogram strategies.
Spread / Pair Differential
Subtract one instrument's normalized price from another to compute the spread in a pairs trading strategy.