Arrow
A complete one-cell arrow adds effective shaft values to the bulb value. A partial arrow adds face digits to at most the bulb’s face-digit number. A bulb with several cells forms a decimal number in the listed order.
Parameters
| Parameter | Meaning | Default |
|---|---|---|
| bulb | The bulb cells, in reading order; several cells form a decimal number. | Required. |
| line | The cells in order, for example r1c1-r1c2-r1c3. | Required. |
| partial | Whether the drawn shaft is only part of the full arrow. | false (complete arrow). |
Maths
Class: with aggregates.
The shared predicates define the notation and every named predicate.
|bulb|>0 ∧ let B = Σ_{i∈[0,|bulb|)} D(bulb[i])*10^(|bulb|-1-i);
(partial → sum_D(line)<=B)
∧ (¬partial → (|bulb|=1 → valueSum(line)=V(bulb[0]))
∧ (|bulb|!=1 → sum_D(line)=B))
A partial shaft always reads face digits and totals at most the bulb’s decimal face-digit number B. A complete one-cell bulb reads effective shaft and bulb values; a complete multi-cell bulb reads digits and totals B.
Example
---
format: open-rules
title: Arrow example
setter: Example
source: ""
case: ""
library: https://rules.sudoku-sleuth.com/
status: read
---
```rules
sudoku 9x9
arrow r1c2-r1c3 bulb ["r1c1"]
```
Satisfies the rule: r1c2=2, r1c3=3, r1c1=5. The shaft digits 2 and 3 total the bulb 5.
Breaks the rule: r1c2=2, r1c3=4, r1c1=5. The shaft digits 2 and 4 total 6, exceeding the bulb 5.