Several markets have zero-production suppliers

[cmutel]

See output from a recent model run for cut-off system model:

Skipping zero total PV with multiple inputs:
market for liquid packaging board/liquid packaging board (GLO, 1 suppliers)
Skipping zero total PV with multiple inputs:
market for cement, pozzolana and fly ash 15-40%, US only/cement, pozzolana and fly ash 15-40%, US only (RoW, 1 suppliers)
Skipping zero total PV with multiple inputs:
market for electricity, low voltage, label-certified/electricity, low voltage, label-certified (RoW, 3 suppliers)
Skipping zero total PV with multiple inputs:
market for electricity, medium voltage, label-certified/electricity, medium voltage, label-certified (RoW, 1 suppliers)
Skipping zero total PV with multiple inputs:
market for cement, blast furnace slag 70-100%, US only/cement, blast furnace slag 70-100%, non-US (RoW, 1 suppliers)
Skipping zero total PV with multiple inputs:
market for waste newspaper/waste newspaper (GLO, 3 suppliers)
Skipping zero total PV with multiple inputs:
market for electricity, high voltage, for Swiss Federal Railways/electricity, high voltage, for Swiss Federal Railways (RoW, 1 suppliers)
Skipping zero total PV with multiple inputs:
market for cement, blast furnace slag 25-70%, US only/cement, blast furnace slag 25-70%, US only (RoW, 1 suppliers)
Skipping zero total PV with multiple inputs:
market for electricity, high voltage, label-certified/electricity, high voltage, label-certified (RoW, 6 suppliers)

This error is being printed by the function allocate_suppliers on line 141. The problem is that there are suppliers to these markets, but they all have zero production volumes.

[pjamesjoyce]

FWIW, the RoW markets in the list are correct - these are exchanges where the entire global production takes place in one region, so there is no RoW market. e.g. the label certified electricity, and the electricity for the railways is only produced in Switzerland, the blast furnace slag cement is US only.

None the wiser on the GLO markets (liquid packaging board and waste newspaper) with zero PV though...

[cmutel]

OK, I guess this makes sense, if you take it as a given that each activity has to have a global equivalent even if it only occurs in one region. Still need to look at specific case to understand why there are multiple suppliers, though.

[cmutel]

Fixed markets with only one supplier in 2e1cd6a.

[cmutel]

Should whitelist known markets which can be either ignored or safely removed, e.g. label-certified electricity.