Source Transit Destination Mesh

Purpose

This calculator draws a two-stage network diagram connecting sources to destinations through an intermediate layer of transits, showing which source-transit and transit-destination pairs are linked. It is useful for visualizing any network with a routing or hub layer in between — such as plants, distribution centers, and customers — and, optionally, for labeling each connection with a value (for example, a shipped quantity or a cost) to review alongside the network.

Background

How the mesh is built

The network has two stages of candidate connections: every possible source-transit pair, and every possible transit-destination pair. The Links input selects which of those candidate connections are actually drawn. Leaving Links blank draws every possible pair in both stages. Custom Labels can attach a value to each candidate connection, whether or not it is drawn — see below for how they are matched.

Inputs

Sources

A comma-separated list of source names (for example, S1, S2, S3).

Transits

A comma-separated list of transit names (for example, T1,T2).

Destinations

A comma-separated list of destination names (for example, D1,D2,D3).

Links

A comma-separated list of Source-Transit and Transit-Destination pairs to draw as edges (for example, S1-T1,T1-D1). Leave this blank to draw every possible source-to-transit and transit-to-destination combination.

Edge Label

When checked, each edge on the diagram is labeled — with its Custom Labels value if one was supplied for that pair, or otherwise with its position number (see Custom Labels below). When unchecked, edges are drawn without a visible label.

Circular

When checked, sources, transits, and destinations are arranged along curved arcs. When unchecked, they are arranged in straight vertical lines. This only affects the layout, not which connections are drawn.

Custom Labels

An optional comma-separated list of values used to label the edges. Values are matched to pairs by position across every possible combination, listed first for every source-transit pair (source by source, and within each source, transit by transit), followed by every transit-destination pair (transit by transit, and within each transit, destination by destination) — including pairs not selected in Links. If fewer labels are supplied than there are combinations, the remaining pairs are left unlabeled.

Results

Chart

The network diagram, showing every drawn source-transit and transit-destination connection as a line between the two nodes, arranged according to Circular, and labeled according to Edge Label and Custom Labels.

Nodes

A table with one row per source, transit, and destination, giving its name and the X, Y position used to place it on the chart.

Edges

A table with one row per drawn connection, giving its From node, its To node, and its Edge label (a position number by default, or the matched Custom Labels value).

Example

With the default inputs — sources S1, S2, S3, transits T1,T2, destinations D1,D2,D3, and every source-transit and transit-destination pair included by default — the chart draws all 6 source-transit connections (S1-T1, S1-T2, S2-T1, S2-T2, S3-T1, S3-T2) followed by all 9 transit-destination connections (T1-D1, T1-D2, T1-D3, T2-D1, T2-D2, T2-D3). Without Custom Labels, the edges are numbered sequentially 0 through 14 in that same order, since every candidate pair is drawn and none are skipped.

Important Assumptions and Interpretation

• Custom Labels are matched purely by position across the full list of source-transit pairs followed by the full list of transit-destination pairs, not by the order connections appear in Links or on the chart — supply enough values, in the right order, to label every intended connection.
• This calculator only draws the network and reports label/position values; it does not calculate flows, costs, or optimal routes. Use the supply-chain optimization calculators (for example, transship_opt) when you need the connections and quantities calculated for you.