Graphs and Relational Learning

Read neighbouring pumps

BOTIE

Gather neighbouring readings with matrix multiplication, then divide each sum by its degree, returning zero for degree zero.
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Context for this challenge

Gather neighbouring readings with matrix multiplication, then divide each sum by its degree, returning zero for degree zero.

Botie wants each pump to read nearby pumps' measurements. An isolated pump has no neighbour average to calculate.

Multiply adjacency by the reading vector, calculate row degrees, and divide sums by degrees with the declared zero fallback.

Examples and results
Binary adjacency matrix
010
101
010
Node readings
  1. 02
  2. 18
  3. 24
Required result
  1. 08
  2. 13
  3. 28
Binary adjacency matrix
01
10
Node readings
  1. 01
  2. 15
Required result
  1. 05
  2. 11
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Assumptions and test precision

The zero fallback is explicit. For directed graphs, choose message orientation before multiplying. Numerical tests allow a difference of 0.001. Lists and structures must also have the right shape.

The hub averages three neighbours

This check uses the pieces from “Gather and average neighbouring readings”.

BOTIE

Four sensors form a star network. Botie wants each sensor's neighbours' mean reading, excluding the sensor's own value. Calculate all four aggregates in node order.
Binary adjacency matrix
0111
1000
1000
1000
Node readings
  1. 010
  2. 12
  3. 24
  4. 39

Use a number, text, or an array matching the requested result. For a matrix, put each row in brackets. Saving your prediction runs your current construction on these inputs and checks the earlier examples too.

Build a construction in the workspace above first. This case will test those pieces.

What metadata would help a later model distinguish an isolated pump from neighbours whose average really is zero?

Make missing-neighbour conventions explicit when carrying aggregated features forward.

The zero fallback is explicit. For directed graphs, choose message orientation before multiplying.

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