Fixed bug in MGXS.get_subdomain_avg(...) with material domain tyeps
Fixed bug in MGXS.get_subdomain_avg(...) with material domain tyeps

mjlong/openmc,samuelshaner/openmc,wbinventor/openmc,samuelshaner/openmc,mit-crpg/openmc,smharper/openmc,walshjon/openmc,johnnyliu27/openmc,bhermanmit/openmc,amandalund/openmc,walshjon/openmc,walshjon/openmc,shikhar413/openmc,smharper/openmc,samuelshaner/openmc,wbinventor/openmc,liangjg/openmc,samuelshaner/openmc,wbinventor/openmc,paulromano/openmc,amandalund/openmc,amandalund/openmc,shikhar413/openmc,shikhar413/openmc,paulromano/openmc,mit-crpg/openmc,mit-crpg/openmc,shikhar413/openmc,liangjg/openmc,wbinventor/openmc,liangjg/openmc,mit-crpg/openmc,amandalund/openmc,smharper/openmc,mjlong/openmc,walshjon/openmc,johnnyliu27/openmc,johnnyliu27/openmc,liangjg/openmc,bhermanmit/openmc,johnnyliu27/openmc,smharper/openmc,kellyrowland/openmc,kellyrowland/openmc,paulromano/openmc,paulromano/openmc