[Lemon-user] Infinity loop problem with CycleCanceling

[meistermicha at gmx.de]

Hello,
I am using the lemon library 1.2.1 to solve a minCostFlow-problem. I encountered a problem by using the cyclecanceling algorithm. Sometimes, depending on graph and flow settings, the function hangs in an infinity loop at cycle_canceling.h at line 935:

while (mmc.findCycleMean() && mmc.cycleCost() < 0) {

I do not have deep insight into the algorithm but by debugging I saw that mmc.cycleCost() returns constantly values around -10e-17. Everything seems to work correctly by changing the line to

while (mmc.findCycleMean() && mmc.cycleCost() < -10e-10) {

Maybe this is a rounding issue?

Regards,
Michael
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