Compare many sources without losing direction.

Problem

A provider set creates too many pairwise stories.

With two providers, it is reasonable to read one comparison result. With five providers, the same question becomes twenty directional comparisons. Looking only at aggregates hides which source was the target, which source was the comparison side, and whether the failure was asymmetric.

That direction matters. A residual in provider A versus provider B means A had target-only duration that B did not cover. The opposite cell asks whether B had target-only duration against A. Both cells can be true over different ranges.

Solution

Build a directional cell for every source pair.

A source matrix keeps source order explicit. Rows are targets. Columns are comparison sources. The diagonal is self-comparison, so it acts as a quick signal that the source had windows for the selected window family. Every non-diagonal cell runs the same overlap, residual, missing, and coverage logic.

var matrix = pipeline.History.CompareSources(
    "Provider matrix",
    "DeviceOffline",
    ["provider-a", "provider-b", "provider-c"]);

var weakCells = matrix.Cells
    .Where(cell => !cell.IsDiagonal)
    .Where(cell => cell.CoverageRatio.GetValueOrDefault(1) < 0.95)
    .ToArray();